U.S. patent application number 12/790317 was filed with the patent office on 2010-09-23 for non-cementitious compositions comprising co2 sequestering additives.
Invention is credited to Brent Constantz, Andrew Youngs.
Application Number | 20100239487 12/790317 |
Document ID | / |
Family ID | 42129297 |
Filed Date | 2010-09-23 |
United States Patent
Application |
20100239487 |
Kind Code |
A1 |
Constantz; Brent ; et
al. |
September 23, 2010 |
NON-CEMENTITIOUS COMPOSITIONS COMPRISING CO2 SEQUESTERING
ADDITIVES
Abstract
Non-cementitious CO.sub.2 sequestering compositions are
provided. The compositions of the invention include a CO.sub.2
sequestering additive, e.g., a CO.sub.2 sequestering carbonate
composition. Additional aspects of the invention include methods of
making and using the non-cementitious CO.sub.2 sequestering
compositions.
Inventors: |
Constantz; Brent; (Portola
Valley, CA) ; Youngs; Andrew; (Los Gatos,
CA) |
Correspondence
Address: |
Calera Corporation;Eric Witt
14600 Winchester Blvd.
Los Gatos
CA
95032
US
|
Family ID: |
42129297 |
Appl. No.: |
12/790317 |
Filed: |
May 28, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12609491 |
Oct 30, 2009 |
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12790317 |
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61110495 |
Oct 31, 2008 |
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61149949 |
Feb 4, 2009 |
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61181250 |
May 26, 2009 |
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Current U.S.
Class: |
423/430 |
Current CPC
Class: |
B01D 53/78 20130101;
C08K 3/26 20130101; C01B 32/50 20170801; B01D 53/1418 20130101;
B01D 2257/504 20130101; Y02P 20/151 20151101; C04B 26/02 20130101;
C01F 5/24 20130101; B01D 2251/40 20130101; Y02P 20/152 20151101;
C01F 11/18 20130101; Y10T 436/23 20150115; C04B 26/02 20130101;
C04B 14/26 20130101; C08K 3/26 20130101; C08L 21/00 20130101 |
Class at
Publication: |
423/430 |
International
Class: |
C01F 11/18 20060101
C01F011/18; C01F 3/00 20060101 C01F003/00; C01F 5/24 20060101
C01F005/24 |
Claims
1. A method of sequestering carbon dioxide, the method comprising:
precipitating a CO.sub.2 sequestering carbonate compound
composition from an alkaline-earth-metal-containing water, wherein
the carbonate compound composition comprises carbon that was
released in the form of CO.sub.2 from the combustion of fuel; and
producing a CO.sub.2 sequestering additive comprising the carbonate
compound composition; and producing a non-cementitious composition
comprising the CO.sub.2 sequestering additive.
2. The method according to claim 1, wherein the
alkaline-earth-metal-containing water is contacted to an industrial
waste stream prior to the precipitating step.
Description
CROSS-REFERENCE
[0001] This application is a divisional of and claims the benefit
of U.S. patent application Ser. No. 12/209,491, titled
"NON-CEMENTITIOUS COMPOSITIONS COMPRISING CO.sub.2 SEQUESTERING
ADDITIVES", filed 30 Oct. 2009, which in turn claims the benefit
of: U.S. Provisional Application No. 61/110,495, titled
"NON-CEMENTITIOUS COMPOSITIONS COMPRISING CO.sub.2 SEQUESTERING
ADDITIVES," filed 31 Oct. 2008; U.S. Provisional Application No.
61/149,949, titled "NON-CEMENTITIOUS COMPOSITIONS COMPRISING
CO.sub.2 SEQUESTERING ADDITIVES," filed 4 Feb. 2009; and U.S.
Provisional Application No. 61/181,250, titled, "COMPOSITIONS AND
METHODS USING SUBSTANCES WITH NEGATIVE DELTA13C VALUES," filed 26
May 2009, which applications are incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] Carbon dioxide (CO.sub.2) emissions have been identified as
a major contributor to the phenomenon of global warming and ocean
acidification. CO.sub.2 is a by-product of combustion and it
creates operational, economic, and environmental problems. It is
expected that elevated atmospheric concentrations of CO.sub.2 and
other greenhouse gases will facilitate greater storage of heat
within the atmosphere leading to enhanced surface temperatures and
rapid climate change. CO.sub.2 has also been interacting with the
oceans driving down the pH toward 8.0. CO.sub.2 monitoring has
shown atmospheric CO.sub.2 has risen from approximately 280 ppm in
the 1950s to approximately 380 pmm today, and is expect to exceed
400 ppm in the next decade. The impact of climate change will
likely be economically expensive and environmentally hazardous.
Reducing potential risks of climate change will require
sequestration of atmospheric CO.sub.2.
SUMMARY OF THE INVENTION
[0003] In some embodiments, the invention provides a
non-cementitious composition that includes a CO.sub.2 sequestering
additive, in which the CO.sub.2 sequestering additive includes
carbon that was released in the form of CO.sub.2 from the
combustion of fuel. In some embodiments, the invention provides a
non-cementitious composition in which the CO.sub.2 sequestering
additive is a carbonate compound. In some embodiments, the
invention provides a non-cementitious composition in which the
carbonate compound composition includes a precipitate from an
alkaline-earth-metal-containing water. In some embodiments, the
invention provides a non-cementitious composition in which the
alkaline-earth-metal-containing water from which the carbonate
compound composition precipitate forms includes CO.sub.2 derived
from an industrial waste stream. In some embodiments, the invention
provides a non-cementitious composition in which the
non-cementitious composition is a paper product. In some
embodiments, the invention provides a non-cementitious composition
in which the non-cementitious composition is a polymeric product.
In some embodiments, the invention provides a non-cementitious
composition in which the non-cementitious composition is a
lubricant. In some embodiments, the invention provides a
non-cementitious composition in which the non-cementitious
composition is an adhesive. In some embodiments, the invention
provides a non-cementitious composition in which the
non-cementitious composition is rubber. In some embodiments, the
invention provides a non-cementitious composition in which the
non-cementitious composition is chalk. In some embodiments, the
invention provides a non-cementitious composition in which the
non-cementitious composition is an asphalt product. In some
embodiments, the invention provides a non-cementitious composition
in which the non-cementitious composition is paint. In some
embodiments, the invention provides a non-cementitious composition
in which the non-cementitious composition is an abrasive for paint
removal. In some embodiments, the invention provides a
non-cementitious composition in which the non-cementitious
composition is a personal care product. In some embodiments, the
invention provides a non-cementitious composition that is a
personal care product in which the personal care product is a
cosmetic. In some embodiments, the invention provides a
non-cementitious composition that is a personal care product in
which the personal care product is a cleaning product. In some
embodiments, the invention provides a non-cementitious composition
that is a personal care product in which the personal care product
is a personal hygiene product. In some embodiments, the invention
provides a non-cementitious composition in which the
non-cementitious composition is an ingestible product. In some
embodiments, the invention provides a non-cementitious composition
that is an ingestible product, in which the ingestible product is a
liquid. In some embodiments, the invention provides a
non-cementitious composition that is an ingestible product, in
which the ingestible product is a solid. In some embodiments, the
invention provides a non-cementitious composition that is an
ingestible product, in which the ingestible product is an animal
ingestible product. In some embodiments, the invention provides a
non-cementitious composition in which the non-cementitious
composition is an agricultural product. In some embodiments, the
invention provides a non-cementitious composition that is an
agricultural product, in which the agricultural product is a soil
amendment product. In some embodiments, the invention provides a
non-cementitious composition that is an agricultural product, in
which the agricultural product is a pesticide. In some embodiments,
the invention provides a non-cementitious composition in which the
non-cementitious composition is an environmental remediation
product. In some embodiments, the invention provides a
non-cementitious composition that is an environmental remediation
product in which the environmental remediation product is forest
soil restoration. In some embodiments, the invention provides a
non-cementitious composition that is an environmental remediation
product in which the environmental remediation product is
neutralization of over-acidified water.
[0004] In some embodiments, the invention provides a method of
producing a non-cementitious composition, in which the method
includes obtaining a CO.sub.2 sequestering additive, in which the
CO.sub.2 sequestering additive includes carbon that was released in
the form of CO.sub.2 from the combustion of fuel and producing a
non-cementitious composition that includes the CO.sub.2
sequestering additive. In some embodiments, the invention provides
a method of producing a non-cementitious composition in which the
CO.sub.2 sequestering additive is a carbonate compound composition.
In some embodiments, the invention provides a method of producing a
non-cementitious composition in which the carbonate compound
composition includes a precipitate from an
alkaline-earth-metal-containing water. In some embodiments, the
invention provides a method of producing a non-cementitious
composition in which the alkaline-earth-metal-containing water
includes CO.sub.2 derived from an industrial waste stream. In some
embodiments, the invention provides a method of producing a
non-cementitious composition in which the non-cementitious
composition is a paper product. In some embodiments, the invention
provides a method of producing a non-cementitious composition in
which the non-cementitious composition is a lubricant. In some
embodiments, the invention provides a method of producing a
non-cementitious composition in which the non-cementitious
composition is an adhesive. In some embodiments, the invention
provides a method of producing a non-cementitious composition in
which the non-cementitious composition is rubber. In some
embodiments, the invention provides a method of producing a
non-cementitious composition in which the non-cementitious
composition is chalk. In some embodiments, the invention provides a
method of producing a non-cementitious composition in which the
non-cementitious composition is an asphalt product. In some
embodiments, the invention provides a method of producing a
non-cementitious composition in which the non-cementitious
composition is paint. In some embodiments, the invention provides a
method of producing a non-cementitious composition in which the
non-cementitious composition is an abrasive for paint removal. In
some embodiments, the invention provides a method of producing a
non-cementitious composition in which the non-cementitious
composition is a personal care product. In some embodiments, the
invention provides a method of producing a non-cementitious
composition that is a personal care product, in which the personal
care product is a cosmetic. In some embodiments, the invention
provides a method of producing a non-cementitious composition that
is a personal care product, in which the personal care product is a
cleaning product. In some embodiments, the invention provides a
method of producing a non-cementitious composition that is a
personal care product, in which the personal care product is a
personal hygiene product. In some embodiments, the invention
provides a method of producing a non-cementitious composition in
which the non-cementitious composition is an ingestible product. In
some embodiments, the invention provides a method of producing a
non-cementitious composition that is an ingestible product, in
which the ingestible product is a liquid. In some embodiments, the
invention provides a method of producing a non-cementitious
composition that is an ingestible product, in which the ingestible
product is a solid. In some embodiments, the invention provides a
method of producing a non-cementitious composition in which the
non-cementitious composition is an animal ingestible product. In
some embodiments, the invention provides a method of producing a
non-cementitious composition in which the non-cementitious
composition is an agricultural product. In some embodiments, the
invention provides a method of producing a non-cementitious
composition that is an agricultural product, in which the
agricultural product is a soil amendment product. In some
embodiments, the invention provides a method of producing a
non-cementitious composition that is an agricultural product, in
which the agricultural product is a pesticide. In some embodiments,
the invention provides a method of producing a non-cementitious
composition in which the non-cementitious composition is an
environmental remediation product. In some embodiments, the
invention provides a method of producing a non-cementitious that is
an environmental remediation product, in which environmental
remediation product is forest soil restoration. In some
embodiments, the invention provides a method of producing a
non-cementitious that is an environmental remediation product, in
which environmental remediation product is neutralization of
over-acidified water.
[0005] In some embodiments, the invention provides a method of
sequestering carbon dioxide that includes precipitating a CO.sub.2
sequestering carbonate compound composition from an
alkaline-earth-metal-containing water, in which the carbonate
compound composition includes carbon that was released in the form
of CO.sub.2 from the combustion of fuel and producing a CO.sub.2
sequestering additive comprising the carbonate compound composition
and producing a non-cementitious composition comprising the
CO.sub.2 sequestering additive. In some embodiments, the invention
provides a method of sequestering carbon dioxide in which the
alkaline-earth-metal-containing water is contacted to an industrial
waste stream prior to the precipitation step.
INCORPORATION BY REFERENCE
[0006] All publications, patents, and patent applications mentioned
in this specification are herein incorporated by reference to the
same extent as if each individual publication, patent, or patent
application was specifically and individually indicated to be
incorporated by reference.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The novel features of the invention are set forth with
particularity in the appended claims. A better understanding of the
features and advantages of the present invention will be obtained
by reference to the following detailed description that sets forth
illustrative embodiments, in which the principles of the invention
are utilized, and the accompanying drawings of which:
[0008] FIG. 1 provides a schematic of a CO.sub.2 sequestering
additive production process according to an embodiment of the
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0009] Non-cementitious CO.sub.2 sequestering compositions are
provided. The compositions of the invention include a CO.sub.2
sequestering additive, e.g., a CO.sub.2 sequestering carbonate
composition. Additional aspects of the invention include methods of
making and using the non-cementitious CO.sub.2 sequestering
compositions.
[0010] Before the present invention is described in greater detail,
it is to be understood that this invention is not limited to
particular embodiments described, as such may, of course, vary. It
is also to be understood that the terminology used herein is for
the purpose of describing particular embodiments only, and is not
intended to be limiting, since the scope of the present invention
will be limited only by the appended claims.
[0011] Where a range of values is provided, it is understood that
each intervening value, to the tenth of the unit of the lower limit
unless the context clearly dictates otherwise, between the upper
and lower limit of that range and any other stated or intervening
value in that stated range, is encompassed within the invention.
The upper and lower limits of these smaller ranges may
independently be included in the smaller ranges and are also
encompassed within the invention, subject to any specifically
excluded limit in the stated range. Where the stated range includes
one or both of the limits, ranges excluding either or both of those
included limits are also included in the invention.
[0012] Certain ranges are presented herein with numerical values
being preceded by the term "about." The term "about" is used herein
to provide literal support for the exact number that it precedes,
as well as a number that is near to or approximately the number
that the term precedes. In determining whether a number is near to
or approximately a specifically recited number, the near or
approximating unrecited number may be a number which, in the
context in which it is presented, provides the substantial
equivalent of the specifically recited number.
[0013] Unless defined otherwise, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention belongs. Although
any methods and materials similar or equivalent to those described
herein can also be used in the practice or testing of the present
invention, representative illustrative methods and materials are
now described.
[0014] All publications and patents cited in this specification are
herein incorporated by reference as if each individual publication
or patent were specifically and individually indicated to be
incorporated by reference and are incorporated herein by reference
to disclose and describe the methods and/or materials in connection
with which the publications are cited. The citation of any
publication is for its disclosure prior to the filing date and
should not be construed as an admission that the present invention
is not entitled to antedate such publication by virtue of prior
invention. Further, the dates of publication provided may be
different from the actual publication dates which may need to be
independently confirmed.
[0015] It is noted that, as used herein and in the appended claims,
the singular forms "a," "an," and "the" include plural references
unless the context clearly dictates otherwise. It is further noted
that the claims may be drafted to exclude any optional element. As
such, this statement is intended to serve as antecedent basis for
use of such exclusive terminology as "solely," "only" and the like
in connection with the recitation of claim elements, or use of a
"negative" limitation.
[0016] As will be apparent to those of skill in the art upon
reading this disclosure, each of the individual embodiments
described and illustrated herein has discrete components and
features which may be readily separated from or combined with the
features of any of the other several embodiments without departing
from the scope or spirit of the present invention. Any recited
method can be carried out in the order of events recited or in any
other order which is logically possible.
[0017] In further describing the subject invention, embodiments of
the non-cementitious CO.sub.2 sequestering compositions, as well as
methods and systems for their production, will be described first
in greater detail. Next, examples of methods of using the CO.sub.2
sequestering compositions will be reviewed further.
Non-Cementitious CO.sub.2 Sequestering Compositions
[0018] Non-cementitious CO.sub.2 sequestering compositions are
provided by the invention. By "CO.sub.2 sequestering composition"
is meant that the composition contains carbon derived from a fuel
used by humans, e.g., carbon having a fossil fuel origin. For
example, CO.sub.2 sequestering compositions according to aspects of
the present invention contain carbon that was released in the form
of CO.sub.2 from the combustion of fuel. In certain embodiments,
the carbon sequestered in a CO.sub.2 sequestering composition is in
the form of a carbonate compound. Therefore, in certain
embodiments, CO.sub.2 sequestering compositions according to
aspects of the subject invention contain carbonate compounds where
at least part of the carbon in the carbonate compounds is derived
from a fuel used by humans, e.g., a fossil fuel. As such,
production of compositions of the invention results in the
placement of CO.sub.2 into a storage stable form, e.g., a stable
component of a non-cementitious composition. Production of the
CO.sub.2 sequestering compositions of the invention thus results in
the prevention of CO.sub.2 gas from entering the atmosphere. The
compositions of the invention provide for storage of CO.sub.2 in a
manner such that CO.sub.2 sequestered (i.e., fixed) in the
composition does not become part of the atmosphere. Compositions of
the invention keep their sequestered CO.sub.2 fixed for
substantially the useful life the composition, if not longer,
without significant, if any, release of the CO.sub.2 from the
composition. As such, where the compositions are consumable
compositions, the CO.sub.2 fixed therein remains fixed for the life
of the consumable, if not longer.
[0019] CO.sub.2 sequestering compositions of the invention include
compositions that contain carbonates and/or bicarbonates, which may
be in combination with a divalent cation such as calcium and/or
magnesium, or with a monovalent cation such as sodium. The
carbonates and/or bicarbonates may be in solution, in solid form,
or a combination of solution and solid form, e.g., a slurry. The
carbonates and/or bicarbonates may contain carbon dioxide from a
source of carbon dioxide; in some embodiments the carbon dioxide
originates from the burning of fossil fuel, and thus some (e.g., at
least 10, 50, 60, 70, 80, 90, 95%) or substantially all (e.g., at
least 99, 99.5, or 99.9%) of the carbon in the carbonates and/or
bicarbonates is of fossil fuel origin, i.e., of plant origin. As is
known, carbon of plant origin has a different ratio of stable
isotopes (.sup.13C and .sup.12C) than carbon of inorganic origin,
and thus the carbon in the carbonates and/or bicarbonates, in some
embodiments, has a .delta..sup.13C of less than, e.g.,
-10.Salinity., or less than -15.Salinity., or less than
-20.Salinity., or less than -35.Salinity., or less than
-30.Salinity., or less than -35.Salinity. as described in further
detail herein below.
[0020] Compositions of the invention include a CO.sub.2
sequestering additive. CO.sub.2 sequestering additives are
components that store a significant amount of CO.sub.2 in a storage
stable format, such that CO.sub.2 gas is not readily produced from
the product and released into the atmosphere. In certain
embodiments, the CO.sub.2 sequestering additives can store 50 tons
or more of CO.sub.2, such as 100 tons or more of CO.sub.2,
including 250 tons or more of CO.sub.2, for instance 500 tons or
more of CO.sub.2, such as 750 tons or more of CO.sub.2, including
900 tons or more of CO.sub.2 for every 1000 tons of composition of
the invention. In certain embodiments, the CO.sub.2 sequestering
additives of the compositions of the invention comprise about 5% or
more of CO.sub.2, such as about 10% or more of CO.sub.2, including
about 25% or more of CO.sub.2, for instance about 50% or more of
CO.sub.2, such as about 75% or more of CO.sub.2, including about
90% or more of CO.sub.2, e.g., present as one or more carbonate
compounds.
[0021] The CO.sub.2 sequestering additives of the invention may
include one or more carbonate compounds. The amount of carbonate in
the CO.sub.2 sequestering additive, as determined by coulometry
using the protocol described in coulometric titration, may be 40%
or higher, such as 70% or higher, including 80% or higher. In some
embodiments, where the Mg source is a mafic mineral (as described
in U.S. Provisional Application Ser. No. 61/079,790, incorporated
by reference herein), or an ash (as described in U.S. Provisional
Application Ser. No. 61/073,319, incorporated herein by reference),
the resultant product may be a composition containing silica as
well as carbonate. In these embodiments, the carbonate content of
the product may be as low as 10%.
[0022] The carbonate compounds of the CO.sub.2 sequestering
additives may be metastable carbonate compounds that are
precipitated from a water, such as a salt-water, as described in
greater detail below. The carbonate compound compositions of the
invention include precipitated crystalline and/or amorphous
carbonate compounds. Specific carbonate minerals of interest
include, but are not limited to: calcium carbonate minerals,
magnesium carbonate minerals and calcium magnesium carbonate
minerals. Calcium carbonate minerals of interest include, but are
not limited to: calcite (CaCO.sub.3), aragonite (CaCO.sub.3),
vaterite (CaCO.sub.3), ikaite (CaCO.sub.3.6H.sub.2O), and amorphous
calcium carbonate (CaCO.sub.3.nH.sub.2O). Magnesium carbonate
minerals of interest include, but are not limited to: magnesite
(MgCO.sub.3), barringtonite (MgCO.sub.3.2H.sub.2O), nesquehonite
(MgCO.sub.3.3H.sub.2O), lanfordite (MgCO.sub.3.5H.sub.2O) and
amorphous magnesium calcium carbonate (MgCO.sub.3.nH.sub.2O).
Calcium magnesium carbonate minerals of interest include, but are
not limited to dolomite (CaMgCO.sub.3), huntite
(CaMg.sub.3(CO.sub.3).sub.4) and sergeevite
(Ca.sub.2Mg.sub.11(CO.sub.3).sub.13.H.sub.2O). In certain
embodiments, non-carbonate compounds like brucite (Mg(OH).sub.2)
may also form in combination with the minerals listed above. As
indicated above, the compounds of the carbonate compound
compositions are metastable carbonate compounds (and may include
one or more metastable hydroxide compounds) that are more stable in
saltwater than in freshwater, such that upon contact with fresh
water of any pH they dissolve and re-precipitate into other fresh
water stable compounds, e.g., minerals such as low-Mg calcite.
[0023] The CO.sub.2 sequestering additives of the invention are
derived from, e.g., precipitated from, a water (as described in
greater detail below). As the CO.sub.2 sequestering products are
precipitated from a water, they may include one or more additives
that are present in the water from which they are derived. For
example, where the water is salt water, the CO.sub.2 sequestering
products may include one or more compounds found in the salt water
source. These compounds may be used to identify the solid
precipitations of the compositions that come from the salt water
source, where these identifying components and the amounts thereof
are collectively referred to herein as a saltwater source
identifier. For example, if the saltwater source is sea water,
identifying compounds that may be present in the precipitated
solids of the compositions include, but are not limited to:
chloride, sodium, sulfur, potassium, bromide, silicon, strontium
and the like. Any such source-identifying or "marker" elements
would generally be present in small amounts, e.g., in amounts of
20,000 ppm or less, such as amounts of 2000 ppm or less. In certain
embodiments, the "marker" compound is strontium, which may be
present in the precipitated incorporated into the aragonite
lattice, and make up 10,000 ppm or less, ranging in certain
embodiments from 3 to 10,000 ppm, such as from 5 to 5000 ppm,
including 5 to 1000 ppm, e.g., 5 to 500 ppm, including 5 to 100
ppm. Another "marker" compound of interest is magnesium, which may
be present in amounts of up to 20% mole substitution for calcium in
carbonate compounds. The saltwater source identifier of the
compositions may vary depending on the particular saltwater source
employed to produce the saltwater-derived carbonate composition.
Also of interest are isotopic markers that identify the water
source.
[0024] Depending on the particular non-cementitious material or
product, the amount of CO.sub.2 sequestering additive that is
present may vary. In some instances, the amount of CO.sub.2
sequestering additive ranges from 5 to 75% w/w, such as 5 to 50%
w/w including 5 to 25% w/w and including 5 to 10% w/w.
[0025] The compositions of the invention may be viewed as
low-carbon footprint compositions. Low-carbon footprint
compositions have a reduced carbon footprint as compared to
corresponding compositions that lack the CO.sub.2 sequestering
additive (where "corresponding" herein means the identical
composition but for the presence of the CO.sub.2 sequestering
additive of the invention). Using any convenient carbon footprint
calculator, the magnitude of carbon footprint reduction of the
compositions of the invention as compared to corresponding
compositions that lack the CO.sub.2 sequestering additive may be 5%
or more, such as 10% or more, including 25%, 50%, 75% or even 100%
or more. In certain embodiments, the low-carbon footprint
compositions of the invention are carbon neutral, in that they have
substantially no, if any, calculated carbon footprint, e.g., as
determined using any convenient carbon footprint calculator that is
relevant for a particular composition of interest. Carbon neutral
compositions of the invention include those compositions that
exhibit a carbon footprint of 50 lbs CO.sub.2/cu yd material or
less, such as 10 lbs CO.sub.2/cu yd material or less, including 5
lbs CO.sub.2/cu yd material or less, where in certain embodiments
the carbon neutral compositions have 0 or negative lbs CO.sub.2/cu
yd material, such as negative 1 or more, e.g., negative 3 or more
lbs CO.sub.2/cu yd material. In some instances, the low carbon
footprint compositions have a significantly negative carbon
footprint, e.g., -100 or more lbs CO.sub.2/cu yd or less.
[0026] In certain embodiments compositions of the invention will
contain carbon from fossil fuel; because of its fossil fuel origin,
the carbon isotopic fractionation (.delta..sup.13C) value of such
compositions will be different from that of compositions containing
inorganic carbon, e.g., limestone. As is known in the art, the
plants from which fossil fuels are derived preferentially utilize
.sup.12C over .sup.13C, thus fractionating the carbon isotopes so
that the value of their ratio differs from that in the atmosphere
in general; this value, when compared to a standard value (PeeDee
Belemnite, or PDB, standard), is termed the carbon isotopic
fractionation (.delta..sup.13C) value. .delta..sup.13C values for
coal are generally in the range -30 to -20.Salinity. and
.delta..sup.13C values for methane may be as low as -20.Salinity.
to -40.Salinity. or even -40.Salinity. to -80.Salinity..
.delta..sup.13C values for atmospheric CO.sub.2 are -10.Salinity.
to -7.Salinity., for limestone +3.Salinity. to -3.Salinity., and
for marine bicarbonate, no. Even if the non-cementitious material
contains some natural limestone, or other source of C with a higher
(less negative) .delta..sup.13C value than fossil fuel, its
.delta..sup.13C value generally will still be negative and less
than (more negative than) values for limestone or atmospheric
CO.sub.2. In some embodiments, the non-cementitious material or
product includes a CO.sub.2-sequestering additive comprising
carbonates, bicarbonates, or a combination thereof, in which the
carbonates, bicarbonates, or a combination thereof have a carbon
isotopic fractionation (.delta..sup.13C) value less than
-5.00.Salinity.. Compositions of the invention thus includes a
non-cementitious material or product with a .delta..sup.13C less
than -10.Salinity., such as less than -12.Salinity., -14.Salinity.,
-16.Salinity., -18.Salinity., -20.Salinity., -22.Salinity.,
-24.Salinity., -26.Salinity., -28.Salinity., or less than
-30.Salinity.. In some embodiments the invention provides a
non-cementitious material or product with a .delta..sup.13C less
than -10.Salinity.. In some embodiments the invention provides a
non-cementitious material or product with a .delta..sup.13C less
than -14.Salinity.. In some embodiments the invention provides a
non-cementitious material or product with a .delta..sup.13C less
than -18.Salinity.. In some embodiments the invention provides a
non-cementitious material or product with a .delta..sup.13C less
than -20.Salinity.. In some embodiments the invention provides a
non-cementitious material or product with a .delta..sup.13C less
than -24.Salinity.. In some embodiments the invention provides a
non-cementitious material or product with a .delta..sup.13C less
than -28.Salinity.. In some embodiments the invention provides a
non-cementitious material or product with a .delta..sup.13C less
than -30.Salinity.. In some embodiments the invention provides a
non-cementitious material or product with a .delta..sup.13C less
than -32.Salinity.. In some embodiments the invention provides a
non-cementitious material or product with a .delta..sup.13C less
than -34.Salinity.. Such a non-cementitious materials or products
may be carbonate-containing materials or products, as described
above, e.g., a non-cementitious material or product with that
contains at least 10, 20, 30, 40, 50, 60, 70, 80, or 90% carbonate,
e.g., at least 50% carbonate w/w.
[0027] The relative carbon isotope composition (.delta..sup.13C)
value with units of .Salinity. (per mil) is a measure of the ratio
of the concentration of two stable isotopes of carbon, namely
.sup.12C and .sup.13C, relative to a standard of fossilized
belemnite (the PDB standard).
.delta..sup.13C
.Salinity.=[(.sup.13C/.sup.12C.sub.sample-.sup.13C/.sup.12C.sub.PDB
standard)/(.sup.13C/.sup.12C.sub.PDB standard)].times.1000
[0028] .sup.12C is preferentially taken up by plants during
photosynthesis and in other biological processes that use inorganic
carbon because of its lower mass. The lower mass of .sup.12C allows
for kinetically limited reactions to proceed more efficiently than
with .sup.13C. Thus, materials that are derived from plant
material, e.g., fossil fuels, have relative carbon isotope
composition values that are less than those derived from inorganic
sources. The carbon dioxide in flue gas produced from burning
fossil fuels reflects the relative carbon isotope composition
values of the organic material that was fossilized. Table 1 lists
relative carbon isotope composition value ranges for relevant
carbon sources for comparison.
[0029] Material incorporating carbon from burning fossil fuels
reflects .delta..sup.13C values that are more like those of plant
derived material, i.e. less, than that which incorporates carbon
from atmospheric or non-plant marine sources. Verification that the
material produced by a carbon dioxide sequestering process is
composed of carbon from burning fossil fuels can include measuring
the .delta..sup.13C value of the resultant material and confirming
that it is not similar to the values for atmospheric carbon
dioxide, nor marine sources of carbon.
TABLE-US-00001 TABLE 1 Relative carbon isotope composition
(.delta..sup.13C) values for carbon sources of interest. Carbon
Source .delta..sup.13C Range [.Salinity.] .delta..sup.13C Average
value [.Salinity.] C3 Plants (most higher -23 to -33 -27 plants) C4
Plants (most tropical -9 to -16 -13 and marsh plants) Atmosphere -6
to -7 -6 Marine Carbonate (CO.sub.3) -2 to +2 0 Marine Bicarbonate
-3 to +1 -1 (HCO.sub.3) Coal from Yallourn Seam -27.1 to -23.2
-25.5 in Australia.sup.1 Coal from Dean Coal Bed -24.47 to -25.14
-24.805 in Kentucky, USA.sup.2 .sup.1Holdgate, G. R. et al., Global
and Planetary Change, 65 (2009) pp. 89-103. .sup.2Elswick, E. R. et
al., Applied Geochemistry, 22 (2007) pp. 2065-2077.
[0030] In some embodiments the invention provides a method of
characterizing a composition comprising measuring its relative
carbon isotope composition (.delta..sup.13C) value. In some
embodiments the composition is a composition that contains
carbonates, e.g., magnesium and/or calcium carbonates. Any suitable
method may be used for measuring the .delta..sup.13C value, such as
mass spectrometry or off-axis integrated-cavity output spectroscopy
(off-axis ICOS).
[0031] One difference between the carbon isotopes is in their mass.
Any mass-discerning technique sensitive enough to measure the
amounts of carbon we have can be used to find ratios of the
.sup.13C to .sup.12C isotope concentrations. Mass spectrometry is
commonly used to find .delta..sup.13C values. Commercially
available are bench-top off-axis integrated-cavity output
spectroscopy (off-axis ICOS) instruments that are able to determine
.delta..sup.13C values as well. These values are obtained by the
differences in the energies in the carbon-oxygen double bonds made
by the .sup.12C and .sup.13C isotopes in carbon dioxide. The
.delta..sup.13C value of a carbonate precipitate from a carbon
sequestration process serves as a fingerprint for a CO.sub.2 gas
source, as the value will vary from source to source, but in most
carbon sequestration cases .delta..sup.13C will generally be in a
range of -9.Salinity. to -35.Salinity..
[0032] In some embodiments the methods further include the
measurement of the amount of carbon in the composition. Any
suitable technique for the measurement of carbon may be used, such
as coulometry.
[0033] Precipitation material, which comprises one or more
synthetic carbonates derived from industrial CO.sub.2, reflects the
relative carbon isotope composition (.delta..sup.13C) of the fossil
fuel (e.g., coal, oil, natural gas, or flue gas) from which the
industrial CO.sub.2 (from combustion of the fossil fuel) was
derived. The relative carbon isotope composition (.delta..sup.13C)
value with units of .Salinity. (per mille) is a measure of the
ratio of the concentration of two stable isotopes of carbon, namely
.sup.12C and .sup.13C, relative to a standard of fossilized
belemnite (the PDB standard).
.delta..sup.13C
.Salinity.=[(.sup.13C/.sup.12C.sub.sample-.sup.13C/.sup.12C.sub.PDB
standard)/(.sup.13C/.sup.12C.sub.PDB standard)].times.1000
[0034] As such, the .delta..sup.13C value of the CO.sub.2
sequestering additive serves as a fingerprint for a CO.sub.2 gas
source. The .delta..sup.13C value may vary from source to source
(i.e., fossil fuel source), but the .delta..sup.13C value for
composition of the invention generally, but not necessarily, ranges
between -9.Salinity. to -35.Salinity.. In some embodiments, the
.delta..sup.13C value for the CO.sub.2 sequestering additive is
between -1.Salinity. and -50.Salinity., between -5.Salinity. and
-40.Salinity., between -5.Salinity. and -35.Salinity., between
-7.Salinity. and -40.Salinity., between -7.Salinity. and
-35.Salinity., between -9.Salinity. and -40.Salinity., or between
-9.Salinity. and -35.Salinity.. In some embodiments, the
.delta..sup.13C value for the CO.sub.2 sequestering additive is
less than (i.e., more negative than) -3.Salinity., -5.Salinity.,
-6.Salinity., -7.Salinity., -8.Salinity., -9.Salinity.,
-10.Salinity., -11.Salinity., -12.Salinity., -13.Salinity.,
-14.Salinity., -15.Salinity., -16.Salinity., -17.Salinity.,
-18.Salinity., -19.Salinity., -20.Salinity., -21.Salinity.,
-22.Salinity., -23.Salinity., -24.Salinity., -25.Salinity.,
-26.Salinity., -27.Salinity., -28.Salinity., -29.Salinity.,
-30.Salinity., -31.Salinity., -32.Salinity., -33.Salinity.,
-34.Salinity., -35.Salinity., -36.Salinity., -37.Salinity.,
-38.Salinity., -39.Salinity., -40.Salinity., -41.Salinity.,
-42.Salinity., -43.Salinity., -44.Salinity., or -45.Salinity.,
wherein the more negative the .delta..sup.13C value, the more rich
the synthetic carbonate-containing composition is in .sup.12C. Any
suitable method may be used for measuring the .delta..sup.13C
value, methods including, but no limited to, mass spectrometry or
off-axis integrated-cavity output spectroscopy (off-axis ICOS).
[0035] The compositions of the invention may vary greatly. By
non-cementitious is meant that the compositions are not settable
compositions, e.g., hydraulic cements. As such, the compositions
are not dried compositions that, when combined with a setting
fluid, such as water, set to produce a solid product. Illustrative
compositions according to certain embodiments of the invention are
now reviewed further in greater detail. However, the below review
of compositions is not limiting on the invention, and is provided
solely to further describe exemplary embodiments of the
invention.
Paper Products
[0036] The present invention includes novel formulations which
incorporate the CO.sub.2 sequestering composition into paper
products. The term "paper products" is employed to refer to a thin
material that is suitable for use in one or more of writing upon,
printing upon or packaging and includes products commonly known as
paper, card stock, and paperboard. Card stock is a type of paper
that is thicker and more durable than paper but more flexible than
paperboard (e.g., cardboard). Paper products of the invention are
produced by pressing together moist fibers (e.g., cellulose,
polymeric) in the form of a pulp composition and then drying the
pressed fibers to form sheets of varying thickness. Paper products
of the invention may be produced in accordance with traditional
manufacturing protocols with the exception that an amount of the
CO.sub.2 sequestering composition is employed. In producing paper
products of the invention, an amount of the CO.sub.2 sequestering
composition may be employed as a filler, absorbent or colorant to
the pulp composition. By "colorant" is meant a compound that is
able to impart a color to a product. Since the CO.sub.2
sequestering precipitate of the invention is inherently white in
color, it is able to improve the white color of already white paper
products, and lighten the color of paper products that are not
white.
[0037] The pulp composition may be derived from components which
include, but are not limited to eucalyptus pulp, banana tree bark,
banana stem-fibers, cotton fibers, vulcanized polymers, cellulose
fibers, animal skin (e.g., calfskin, sheepskin, goatskin), papyrus,
high density polyethylene fibers, hemp, bamboo, grass, rags or pulp
derived from the wood of any suitable tree. The moisture content of
the pulp composition may vary, ranging from 5% to 10%, such as 6%
and including 7%. In some instances, the CO.sub.2 sequestering
composition may be added to the pulp composition as an absorbent in
order to decrease the moisture content in the paper.
[0038] The density of paper products of the invention may vary
greatly. The density of "paper" ranges from 100 kg/m.sup.3 to 1500
kg/m.sup.3, such as 250 kg/m.sup.3 to 1250 kg/m.sup.3, including
500 kg/m.sup.3 to 800 kg/m.sup.3. The density of "papercard" or
"card stock" ranges from 1500 kg/m.sup.3 to 3000 kg/m.sup.3, such
as 1700 kg/m.sup.3 to 2500 kg/m.sup.3, and including 2000
kg/m.sup.3 to 2250 kg/m.sup.3. The density of "paperboard" can be
3000 kg/m.sup.3 and denser, such as 3500 kg/m.sup.3 and denser,
including 5000 kg/m.sup.3 and denser. The thickness of paper
products the invention may also vary greatly. The thickness of
"paper" ranges between 0.05 mm to 0.18 mm, such as 0.07 mm to 0.18
mm and including 0.1 mm to 0.15 mm. The thickness of "papercard"
ranges between 0.18 mm to 0.25 mm, such as 0.18 mm to 0.2 mm and
including 0.19 mm. The thickness of "paperboard" may be 0.25 mm and
thicker, such as 0.3 mm and thicker, and including 1 mm and
thicker. The weight of paper products of the invention may vary. By
"weight" is meant the mass of paper product per unit area, usually
measured in g/m.sup.2. The weight of "paper" may range between 20
g/m.sup.2 to 160 g/m.sup.2, such as 60 g/m.sup.2 to 150 g/m.sup.2
and including 80 g/m.sup.2 to 120 g/m.sup.2. The weight of
"papercard" may range between 160 g/m.sup.2 to 500 g/m.sup.2, such
as 175 g/m.sup.2 to 400 g/m.sup.2 and including 200 to g/m.sup.2 to
300 g/m.sup.2. The weight of "paperboard" may range from 500
g/m.sup.2 and heavier, such as 750 g/m.sup.2 and heavier and
including 2000 g/m.sup.2 and heavier.
[0039] In manufacturing paper products of the invention, the pulp
composition precursors of the paper products may include one or
more additional components, such as sizing agents, additional
fillers (e.g., clay, china) and pigments. The amount of CO.sub.2
sequestering additive in the finished paper product may vary, and
may be 1% by weight or more, such as 3% by weight or more,
including 5% by weight or more. During manufacture, following
production of the pulp with the CO.sub.2 sequestering additive, the
pulp may be pressed, dried and cut as desired to produce a product
of desired dimensions. The paper may also be modified (e.g.,
bleached, treated with a sizing agent or surface coating) after the
finished paper product has been produced.
Polymeric Products
[0040] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into polymeric
products. The CO.sub.2 sequestering additive may be present in the
polymeric product in various amounts, as desired, and may be
present as fillers and/or other purposes. As such, the amount of
CO.sub.2 sequestering additive in the polymeric composition may
vary, and may be 1% by weight or more, such as 3% by weight or
more, including 5% by weight or more. In certain embodiments, the
polymeric products are plastics. The term "plastic" is used in its
common sense to refer to a wide range of synthetic or semisynthetic
organic solid materials suitable for the manufacture of industrial
products (e.g., films, fibers, plates, tubes, bottles, boxes).
Plastics may be polymers of high molecular weight, and may contain
other substances to improve performance which may include but are
not limited to acid scavengers, antimicrobial agents, antioxidants,
antistatic agents, antifungal agents, clarifying agents, flame
retardants, amine light stabilizers, UV absorbers, optical
brighteners, photoselective additives, processing stabilizers, and
the like. Plastics of the invention may be acrylics, polyesters,
silicones, polyurethanes or halogenated plastics. Plastics of
interest include, but are not limited to: polypropylenes (e.g., as
employed in food containers, appliances, car bumpers), polystyrenes
(e.g., as employed in packaging foam, food containers, disposable
cups, plates, cutlery, CD and cassette boxes), high impact
polystyrenes (e.g., as employed in fridge liners, food packaging,
vending cups), acrylonitrile butadiene styrene (e.g., as employed
in electronic equipment cases such as computer monitors, printers,
keyboards), polyethylene terephthalates (e.g., as employed in
carbonated drinks bottles, jars, plastic film, microwavable
packaging), polyesters (e.g., as employed in fibers, textiles),
polyamides (e.g., as employed in fibers, toothbrush bristles,
fishing line, under-the-hood car engine mouldings), poly(vinyl
chloride) (e.g., as employed in plumbing pipes and guttering,
shower curtains, window frames, flooring), polyurethanes (e.g., as
employed in cushioning foams, thermal insulation foams, surface
coatings, printing rollers) polycarbonates (e.g., as employed in
compact discs, eyeglasses, riot shields, security windows, traffic
lights, lenses), polyvinylidene chloride (e.g., as employed in food
packaging, saran), polyethylene (e.g., as employed in supermarket
bags, plastic bottles) and polycarbonate/acrylonitrile butadiene
styrene (e.g., as employed in car interior and exterior parts).
Polymeric products, such as plastics, of the invention may be
prepared in accordance with traditional manufacturing protocols for
such compositions, with the exception that an amount of CO.sub.2
sequestering additive of the invention is employed. As such, an
amount of the CO.sub.2 sequestering additive may be combined with
other additives of the plastic precursor composition or feed, and
then molded, cast, extruded into the final desired plastic
product.
Lubricants
[0041] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into lubricants.
The CO.sub.2 sequestering composition may be present in the
lubricants in various amounts, as desired, and may be present as
fillers and/or other purposes. The amount of CO.sub.2 sequestering
additive in the lubricant may vary, and may be 1% by weight or
more, such as 3% by weight or more, including 5% by weight or more.
The lubricating oil composition may be formulated for commercial
purposes for use in internal combustion engines, such as gasoline
and diesel engines, crankcase lubrication and the like. The oil
(sometimes referred to as "base oil") is an oil of lubricating
viscosity and is the primary liquid constituent of a lubricant,
into which additives and possibly other oils are blended to produce
the final lubricant (herein "lubricating composition"). A base oil
may be selected from natural (vegetable, animal or mineral) and
synthetic lubricating oils and mixtures thereof. It may range in
viscosity from light distillate mineral oils to heavy lubricating
oils such as gas engine oil, mineral lubricating oil, motor vehicle
oil, and heavy duty diesel oil. In some instances, the viscosity of
the oil ranges from 2 to 30 mm.sup.2s.sup.-1, such as 5 to 20
mm.sup.2s.sup.-1 at 100.degree. C.
[0042] Natural oils include animal oils and vegetable oils, liquid
petroleum oils and hydrorefined, solvent-treated or acid-treated
mineral lubricating oils of the paraffinic, naphthenic and mixed
paraffinic-naphthenic types. Oils of lubricating viscosity derived
from coal or shale are also useful base oils. Synthetic lubricating
oils include hydrocarbon oils and halo-substituted hydrocarbon oils
such as polymerized and interpolymerized olefins (e.g.,
polybutylenes, polypropylenes, propylene-isobutylene copolymers,
chlorinated polybutylenes, poly(1-hexenes), poly(1-octenes),
poly(1-decenes)); alkylbenzenes (e.g., dodecylbenzenes,
tetradecylbenzenes, dinonylbenzenes, di(2-ethylhexyl)benzenes);
polyphenyls (e.g., biphenyls, terphenyls, alkylated polyphenols);
and alkylated diphenyl ethers and alkylated diphenyl sulfides and
the derivatives; analogs and homologs thereof. Alkylene oxide
polymers and interpolymers and derivatives thereof where the
terminal hydroxyl groups have been modified, for example by
esterification or etherification, constitute another class of known
synthetic lubricating oils. Another suitable class of synthetic
lubricating oils comprises the esters of dicarboxylic acids. Esters
useful as synthetic oils also include those made from C.sub.5 to
C.sub.12 monocarboxylic acids and polyols, and polyol ethers such
as neopentyl glycol, trimethylolpropane, pentaerythritol,
dipentaerythritol and tripentaerythritol. Silicon-based oils such
as the polyalkyl-, polyaryl-, polyakoxy-, or polyaryloxysiloxane
oils and silicate oils comprise another useful class of synthetic
lubricants.
[0043] Unrefined, refined and rerefined oils can be used in the
lubricants of the present invention. Unrefined oils are those
obtained directly from a natural or synthetic source without
further purification treatment. For example, a shale oil obtained
directly from retorting operations, a petroleum oil obtained
directly from distillation or ester oil obtained directly from an
esterification process and used without further treatment would be
an unrefined oil. Refined oils are similar to the unrefined oils
except they have been further treated in one or more purification
steps to improve one or more properties. Many such purification
techniques, such as distillation, solvent extraction, acid or base
extraction, filtration and percolation are known to those skilled
in the art. Rerefined oils are obtained by processes similar to
those used to obtain refined oils applied to refined oils which
have been already used in service. Such rerefined oils are also
known as reclaimed or reprocessed oils and often are additionally
processed by techniques for removal of spent additives and oil
breakdown products. Also present may be one or more co-additives.
Known additives may be incorporated into the lubricant composition
together with the additives of the invention. They may, for
example, include dispersants; other detergents, e.g. single or
mixed detergent systems; rust inhibitors; anti-wear agents;
anti-oxidants; corrosion inhibitors; friction modifiers or friction
reducing agents; pour point depressants; anti-foaming agents;
viscosity modifiers; and surfactants. They can be combined in
proportions known in the art. Some additives can provide a
multiplicity of effects; thus, for example, a single additive may
act as a dispersant and as an oxidation inhibitor.
[0044] In certain instances, the additive is a dispersant. A
dispersant is an additive for a lubricant whose primary function is
to hold solid and liquid contaminants in suspension, thereby
passivating them and reducing engine deposits at the same time as
reducing sludge depositions. Thus, for example, a dispersant
maintains in suspension oil-insoluble substances that result from
oxidation during use of the lubricant, thus preventing sludge
flocculation and precipitation or deposition on metal parts of the
engine. Dispersants are usually "ashless", being non-metallic
organic materials that form substantially no ash on combustion, in
contrast to metal-containing, and hence ash-forming, materials.
They comprise a long chain hydrocarbon with a polar head, the
polarity being derived from inclusion of, e.g. an O, P or N atom.
The hydrocarbon is an oleophilic group that confers oil-solubility,
having for example 40 to 500 carbon atoms. Thus, ashless
dispersants may comprise an oil-soluble polymeric hydrocarbon
backbone having functional groups that are capable of associating
with particles to be dispersed. Typically, the dispersants comprise
amine, alcohol, amide, or ester polar moieties attached to the
polymer backbone often via a bridging group. The ashless dispersant
may be, for example, selected from oil-soluble salts, esters,
amino-esters, amides, imides, and oxazolines of long chain
hydrocarbon-substituted mono- and dicarboxylic acids or their
anhydrides; thiocarboxylate derivatives of long chain hydrocarbons;
long chain aliphatic hydrocarbons having a polyamine attached
directly thereto, and Mannich condensation products formed by
condensing a long chain substituted phenol with formaldehyde and
polyalkylene polyamine, such as described in U.S. Pat. No.
3,442,808. Dispersants include, for example, derivatives of long
chain hydrocarbon-substituted carboxylic acids, examples being
derivatives of high molecular weight hydrocarbyl-substituted
succinic acid.
[0045] A noteworthy group of dispersants are
hydrocarbon-substituted succinimides, made, for example, by
reacting the above acids (or derivatives) with a
nitrogen-containing compound, advantageously a polyalkylene
polyamine, such as a polyethylene polyamine. Particularly preferred
are the reaction products of polyalkylene polyamines with alkenyl
succinic anhydrides, such as described in U.S. Pat. Nos. 3,202,678;
3,154,560; 3,172,892; 3,024,195, 3,024,237; 3,219,666; and
3,216,936; and BE-A-66,875 that may be post-treated to improve
their properties, such as borated (as described in U.S. Pat. Nos.
3,087,936 and 3,254,025) fluorinated and oxylated. For example,
boration may be accomplished by treating an acyl
nitrogen-containing dispersant with a boron compound selected from
boron oxide, boron halides, boron acids and esters of boron acids.
Also of interest are Anti-Wear and Anti-Oxidant Agents.
Dihydrocarbyl dithiophosphate metal salts are frequently used in
lubricants as anti-wear and antioxidant agents. The metal may be an
alkali or alkaline earth metal, or aluminum, lead, tin, zinc,
molybdenum, manganese, nickel or copper. The zinc salts are most
commonly used in lubricating oil in amounts of 0.1 to 10,
preferably 0.2 to 2, mass %, based upon the total weight of the
lubricant. They may be prepared in accordance with known techniques
by first forming a dihydrocarbyl dithiophosphoric acid (DDPA),
usually by reaction of one or more alcohols or a phenol with
P.sub.2S.sub.5 and then neutralising the formed DDPA with a zinc
compound. The zinc dihydrocarbyl dithiophosphates can be made from
mixed DDPA which in turn may be made from mixed alcohols.
Alternatively, multiple zinc dihydrocarbyl dithiophosphates can be
made and subsequently mixed. Lubricants of the invention may be
prepared in accordance with traditional manufacturing protocols for
such compositions, with the exception that an amount of CO.sub.2
sequestering additive of the invention is employed. As such, an
amount of the CO.sub.2 sequestering additive may be combined with
other components of the lubricant and combined into the final
desired lubricant product.
Adhesives
[0046] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into adhesives.
By "adhesives" is meant compounds that adhere to a substrate or
bond two substrates together. Adhesives of the invention may be
produced in accordance with traditional manufacturing protocols
with the exception that an amount of the CO.sub.2 sequestering
composition is employed. In producing adhesives of the invention,
an amount of the CO.sub.2 sequestering composition may be employed
as colorants, fillers, and to improve rheology and increase tensile
strength.
[0047] The physical properties of adhesives of the invention may
vary greatly depending upon the type of chemical system employed
and the amount of the CO.sub.2 sequestering composition added. The
viscosity may range from 1.0 cP to 750000 cP, such as 100 cP to
10000 cP, including 500 cP to 5000 cP, and including 1500 cP to
3000 cP. The effective temperature of the adhesive may range
between -75.degree. C. to 500.degree. C., such as 0.degree. C. to
200.degree. C. and including 50.degree. C. to 150.degree. C. By
"effective temperature" is meant the temperature range in which the
adhesive shows no significant changes in its physical properties or
utility (i.e., insignificant change in substrate bonding). The
tensile strength of the adhesive may range from 0.1 MPa to 75 MPa,
such as 10 MPa to 50 MPa and including 15 to 35 MPa. The elongation
capacity of the adhesives may range from 1.0% to 150%, such as 40%
to 100% and including 50% to 75%.
[0048] When added, the CO.sub.2 sequestering composition may
increase the viscosity, the storage and loss moduli of the
adhesive, and in some instances, impart pseudoplasticity and
thixotropy. The amount of CO.sub.2 sequestering composition in
adhesives of the invention may vary, ranging from 5 to 40% by
weight, such as 5 to 25% by weight and including 10 to 15% by
weight.
[0049] Adhesives of the invention may be natural or synthetic.
Natural adhesives are made from inorganic mineral sources or
biological sources such as vegetable matter, dextrin or other
natural resins. Synthetic adhesives usually comprise a chemical
system (e.g., polymeric material), binders (e.g., polyester,
polyurethane, acrylic resin), an aqueous or organic solvent and one
or more additives. Exemplary chemical systems may include
polyoxymethylene, acrylic, polyacrylate, bismaleimide, butyl,
cyanoacrylate, epoxy, ethylene copolymer, fluoropolymer,
polyisoprene, polyamide, polyphenylene sulfide, polysulfide,
polypropylene, polybutadiene, polyolefinic, polyester,
polyurethane, polyphenolic, silicone, starch, polystyrene, styrene
copolymer, vinyl, polyvinylcarbonate, rubber, elastomer, and
compatible mixtures thereof.
[0050] In some embodiments, adhesives of the invention may be
liquid compositions which employ a solvent. Exemplary solvents may
include, but are not limited to xylene, methanol, toluene, mineral
spirits, acetone, butyl acetate, brominated solvents, mixtures
thereof, among others. The amount of solvent comprises about 10% to
90% of the liquid composition, such as 50% to 75%, including 60% to
70%. The liquid composition may be applied by brushing, spraying,
rolling, immersing the substrate into the composition, or any other
convenient method for applying a coating to a surface. In some
instances, depending on the amount of solvent, the liquid adhesive
composition may be employed as a caulk or sealant.
[0051] In other instances, the liquid adhesive composition may be
dispensed using an aerosol sprayer by formulating the adhesive with
a suitable propellant. Exemplary propellants include, but are not
limited to fluorinated propellants such as HFCs, hydrocarbons such
as propane, butane, isobutane, pentane, nitrogen, carbon dioxide
and any compatible mixtures thereof. The amount of propellant may
vary, ranging from 10% to 30%, such as 15% to 25%, including 15% to
20%. The composition, including the sprayable propellant may be
packaged into an aerosol by any convenient protocol.
[0052] In other embodiments, adhesives of the invention may be
viscous liquids, gels, soft solids or powders. In producing the
viscous liquid, soft solid, solid and gel adhesives, the components
may be blended and mixed using any convenient protocol. Exemplary
methods for blending the components include but are not limited to
banbury mixers, sigman blade mixers, double arm mixers, vortexing
mixers, mixers that employ sonication, mixers that employ heavy
agitation, among others. Solid, soft solid and gel adhesives of the
invention may then be further shaped by extruding, rotary pressing,
stamping, cutting, laminating or molding to produce the final
adhesive product. In manufacturing adhesives of the invention, the
above mentioned constituents may also include one or more
additional components, such as anti-foaming agents, wetting agents,
thickeners, plasticizers, antioxidants and metal chelating agents.
Tackifiers which increase the adhesion of the compositions in
general or for specific surfaces may also be added. Exemplary
tackifiers include polyterpene resins, gum rosin, rosin esters and
other rosin derivatives, oil-soluble phenolic resins,
coumaroneindene resins and petroleum hydrocarbon resins.
[0053] Methods of setting (i.e., curing) the adhesive product may
include air drying, anaerobic drying, thermoplastic setting,
thermoset, two-component setting, UV or radiation cured, pressure
induced setting, single component setting, moisture cured and
vulcanization.
[0054] Adhesives of the invention may be compatible with use on a
number of different types of substrates including but not limited
to ceramic, glass, concrete, masonry, composite materials, metal,
paper or paperboard, plastic, porous surfaces, rubber, elastomer,
textiles, fabrics or wood.
Rubber
[0055] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into rubber. The
term "rubber" is used in its conventional sense to mean an elastic
material of varying chemical composition which comprise long
thread-like molecules and possess a flexibility in its molecular
chain to allow for overall material flexing and coiling. Rubber of
the invention may be produced in accordance with traditional
manufacturing protocols with the exception that an amount of the
CO.sub.2 sequestering composition is employed. In producing rubber
of the invention, an amount of the CO.sub.2 sequestering
composition may be employed as colorants, fillers and to improve
workability of the raw rubber product. Rubber of the invention may
be natural or synthetic. The term "natural" refers to rubber in the
form of a hydrocarbon polymer of isoprene units derived from the
milky colloidal suspension from the sap of a rubber tree or other
such plants. Synthetic rubber may be derived from a number of
different synthetic polymers including, but not limited to
poly-styrene-butadiene, polyisobutylene, ethylene-propylene
copolymer, polyneoprene, butadiene-acrylonitrile copolymer,
fluoroelastomers, polyurethane, polysulfide, polyacrylate among
others. Rubber of the invention may also include one or more
additives, which include a vulcanizing agent, a vulcanization
accelerator, a process oil, an anti-aging agent, an antioxidant and
an anti-ozonant. In producing rubber of the invention, the
components may be blended or mixed with the CO.sub.2 sequestering
composition using any convenient protocol. Exemplary methods for
blending the compositions include banbury mixers, sigman blade
mixers, double-arm mixers, vortexing mixers, mixers that employ
sonication, mixers that employ heavy agitation, among others. The
rubber may be further shaped by rotary pressing, extruding,
stamping, cutting, molding or any other convenient protocol into
the final rubber product.
Chalk
[0056] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into chalk. The
term "chalk" is used in its conventional sense to refer to a
marking element usually in the form of a stick or block used for
writing or drawing on a rough surface. Chalk in the present
invention is a mixture of an amount of the CO.sub.2 sequestering
composition with one or more thermosetting synthetic binders which
is further processed into the form of sticks or blocks. Binders
used in the production of chalk may be any conventional
thermosetting synthetic binder. Exemplary binders include uncured
epoxy, polyester, polyurethane or acrylic resins, or compatible
mixtures thereof. Sticks or blocks of chalk are produced by forming
a uniform mixture of the CO.sub.2 sequestering composition with the
synthetic binder and pressing it under high pressure at room
temperature. The procedure is preferably such that the mixture of
components are processed in an extrusion press, cooled and crushed
to a fine particle size, such as 100 microns or smaller, including
75 microns or smaller and preferably 60 microns or smaller. The
pulverulent mixture of components obtained is then pressed at room
temperature and under a pressure sufficient to consolidate the
powder (e.g., 10-35 MPa) into sticks or blocks of chalky and
friable consistency. Smaller sticks or blocks may also be cut from
larger pre-pressed blocks. Colored chalk may also be produced using
the above described method, with the exception that a colorant
(i.e., dye) may be added to the CO.sub.2 sequestering composition
and binder mixture.
Asphalt Products
[0057] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into asphalt
products. The term "asphalt" (i.e., bitumen) is used in its
conventional sense to refer to the natural or manufactured black or
dark-colored solid, semisolid or viscous material composed mainly
of high molecular weight hydrocarbons derived from a cut in
petroleum distillation after naptha, gasoline, kerosene and other
fractions have been removed from crude oil.
[0058] The molecular composition of asphalt products may vary.
Asphalt products of the invention may be composed of saturated and
unsaturated aliphatic and aromatic compounds that possess
functional groups that include, but are not limited to alcohol,
carboxyl, phenolic, amino, thiol functional groups. In an exemplary
embodiment, asphalt products may be 80% carbon by weight, 10%
hydrogen by weight, 6% sulfur by weight, 3% total weight of oxygen
and nitrogen; and may also include trace amounts of various metals
such as iron, nickel and vanadium. The molecular weight of asphalt
products may range from 0.2 kDa to 50 kDa, such as 1 kDa to 25 kDa,
including 2 kDa to 10 kDa. Components of asphalts may be
asphaltenes (i.e., high molecular weight compounds that are
insoluble in hexane or heptane) or maltenes (i.e., lower molecular
weight compounds that are soluble in hexane or heptane). The amount
of asphaltenes in asphalt products may vary, ranging from 5% to 25%
by weight, such as 10% to 20%, and including 12% to 15%. In some
embodiments, asphalt products of the invention may also contain a
polymeric additive to enhance workability, viscoelasticity, and
strain recovery. Exemplary polymeric additives include
polybutadiene, polyisoprene, ethylene/vinyl acetate copolymer,
polyacrylate, polymethacrylate, polychloroprene, etc. Asphalt
products of interest also include an amount of aggregate. Aggregate
of the invention may be any convenient aggregate material. The
aggregate material may be CO.sub.2 sequestering aggregates, for
example as described in U.S. patent application Ser. No.
12/475,378, titled "ROCK AND AGGREGATE, AND METHODS OF MAKING AND
USING THE SAME"; the disclosure of which is herein incorporated by
reference.
[0059] Asphalt products of the invention may be prepared in
accordance with traditional manufacturing protocols, with the
exception that an amount of the CO.sub.2 sequestering composition
of the invention is employed. The amount of CO.sub.2 sequestering
additive, e.g., present in the asphalt product may vary, and may be
1% by weight or more, such as 3% by weight or more, including 5% by
weight or more, such as 25% by weight or more, 50% by weight or
more, 75% by weight or more. As such, an amount of the CO.sub.2
sequestering additive may be combined with other components of the
asphalt product (e.g., asphalt, aggregate, cutback solvents,
polymeric additives), and then mixed to produce the final asphalt
product.
Paint
[0060] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into paint. By
"paint" is meant any liquid, liquefiable, or mastic composition
which, after application to a substrate in a thin layer, is
converted to an opaque solid film. Paints may include one or more
of the following components: pigments, binders, solvents and
additives. Pigments are granular solids incorporated into the
paint, e.g., to contribute color, toughness or simply to reduce the
cost of the paint. Pigments of interest include natural and
synthetic types. Natural pigments include various clays, calcium
carbonate, mica, silicas, and talcs. Synthetic pigments include
engineered molecules, calcined clays, blanc fix, precipitated
calcium carbonate, and synthetic silicas. Hiding pigments, in
making paint opaque, also protect the substrate from the harmful
effects of ultraviolet light. Hiding pigments include titanium
dioxide, phthalo blue, red iron oxide, and many others. Fillers are
a special type of pigment that serve to thicken the film, support
its structure and simply increase the volume of the paint. Fillers
of interest include inert materials, such as talc, lime, baryte,
clay, etc. Floor paints that will be subjected to abrasion may even
contain fine quartz sand as a filler. Not all paints include
fillers. On the other hand some paints contain very large
proportions of pigment/filler and binder. The CO.sub.2 sequestering
additive of the invention may be employed in place of all or some
of the above pigment components in a given paint. The binder, or
resin, is the actual film forming component of paint. The binder
imparts adhesion, binds the pigments together, and strongly
influences such properties as gloss potential, exterior durability,
flexibility, and toughness. Binders of interest include synthetic
or natural resins such as acrylics, polyurethanes, polyesters,
melamine resins, epoxy, or oils, etc. Solvents of interest may be
present, e.g., to adjust the viscosity of the paint. They may be
volatile so as not to become part of the paint film. Solvents may
be included to control flow and application properties, and affect
the stability of the paint while in liquid state. Solvents of
interest include water, e.g., water-based paints and organic
solvents, e.g., aliphatics, aromatics, alcohols, and ketones.
Organic solvents such as petroleum distillate, esters, glycol
ethers, and the like find use. Additives of interest include
additives to modify surface tension, improve flow properties,
improve the finished appearance, increase wet edge, improve pigment
stability, impart antifreeze properties, control foaming, control
skinning, etc. Other types of additives include catalysts,
thickeners, stabilizers, emulsifiers, texturizers, adhesion
promoters, UV stabilizers, flatteners (de-glossing agents),
biocides to fight bacterial growth, and the like.
[0061] Paint products of the invention may be prepared in
accordance with traditional manufacturing protocols with the
exception that an amount of CO.sub.2 sequestering additive of the
invention is employed. The amount of CO.sub.2 sequestering additive
in the paint may vary, and may be 1% by weight or more, such as 3%
by weight or more, including 5% by weight or more, such as 25% by
weight or more. As such, an amount of the CO.sub.2 sequestering
additive may be combined with other components of the paint such as
pigment, binder, solvent, additive and then mixed to produce the
final paint product.
Personal Care, Cleaning and Other Non-Ingestible Products
[0062] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into
non-ingestible products. By "non-ingestible" is meant compounds
that are not suitable for consumption. Of interest are novel
non-ingestible formulations which incorporate the CO.sub.2
sequestering composition of the invention into personal care
products. Personal care products of the invention are compositions
intended for cleaning purposes or personal use such as for health
and/or hygiene purposes. Personal care products may be products
that relate to sun-care (e.g., sunscreens, sun-tan lotion, self
tanning compositions, bronzers), baby-care (e.g., diapers, baby
wipes, baby powder, diaper rash products), facial and body
treatment (e.g., acne prevention wipes, acne treatment cream,
facial cleansing soap and exfoliating soap, antiperspirants,
deodorants, aftershave lotion, bath soap, bath wash, shaving cream,
shaving gel, makeup removal, moisturizers, anti-wrinkle creams,
lotions), foot-care (anti-itch cream, anti-fungal creams),
oral-care (toothpaste, mouthwash), hair-care (shampoo, conditioner,
hair spray, hair gel, mouse, colorants, depilatory treatments, hair
bleach) and First Aid (bandages, antiseptic sprays, antibacterial
gels). Another type of personal care product is cosmetics.
Cosmetics of the invention are makeup products that include, but
are not limited to mascara, eyeshadow, eyeliner, blush, concealer,
foundation, face powder, lipstick, lip gloss, lip treatment,
lipliner and nail polish. Another type of personal care product are
cleaning products. Cleaning products of the invention are compounds
used primarily in the removal of dirt, stains, impurities,
microorganisms and the like. Cleaning products of the invention may
be products that relate to laundry cleaners (e.g., laundry
detergent, stain remover, fabric softener), dishwashing products
(dishwashing liquid, dishwashing powders, dishwashing gels, rinse
agents, fast-dry agents), room deodorizing products, bathroom
cleaners (toilet, shower, marble, porcelain), powdered bleach, shoe
polish and all-purpose cleaners.
[0063] The CO.sub.2 sequestering composition of the invention may
be employed in non-ingestible products as an abrasive, absorbent,
buffering agent, filler, anti-caking agent, colorant, opacifying
agent, UV-scattering agent or oral care agent. Traditional
abrasives, absorbents, buffering agents, fillers, colorants,
anti-caking agents, opacifying agents, UV-scattering agents or oral
care agents that are conventionally found in non-ingestible
products may be substituted entirely or a certain amount removed
and replaced using the CO.sub.2 sequestering composition of the
present invention. The CO.sub.2 sequestering composition used to
replace traditional additives may be present in amounts such as 1%
by weight or more, such as 3% by weight or more, including 5% by
weight or more, such as 25% by weight or more, 50% by weight or
more, 75% by weight or more.
[0064] In some embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in non-ingestible products as an
abrasive. By "abrasive" is meant a compound that contains an amount
of roughness which when used on a surface is able to abrade,
smooth, buff, polish, grind and the like. The roughness of the
abrasive may vary, depending on the particle sizes of the CO.sub.2
sequestering composition. In some instances, the particle sizes of
the CO.sub.2 sequestering composition are small (.ltoreq.0.5
micron) and may be incorporated into non-ingestible products where
only a mild abrasive is desired (e.g., bathroom cleaners, baby
wipes). In other instances, the particle sizes of the CO.sub.2
sequestering precipitate are large (.gtoreq.5 micron) and may be
incorporated into non-ingestible products where a strong abrasive
is desired (e.g., bath soap, toothpaste). Exemplary non-ingestible
products of the invention employing the CO.sub.2 sequestering
composition as an abrasive include toothpaste, shoe polish,
mouthwash, facial cleansing soaps, exfoliating products, acne
prevention wipes, bath soap, bath wash, makeup remover, baby wipes,
diaper rash products, bathroom cleaners, powdered bleach and all
purpose cleaners. In some embodiments, the CO.sub.2 sequestering
composition is employed as an abrasive for paint removal, such as
in processes employing blasting techniques wherein the abrasive is
suspended in a liquid and applied to a painted or coated surface.
The CO.sub.2 sequestering composition may be used as an abrasive
for paint removal in cases where the surfaces are delicate, such as
lightweight metal and plastic surfaces, in some embodiments of the
invention.
[0065] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in non-ingestible products as an
absorbent. By "absorbent" is meant a compound that possesses the
capacity to absorb or soak up liquids (i.e., drying agent).
Exemplary non-ingestible products of the invention employing the
CO.sub.2 sequestering composition as an absorbent include
eyeshadow, blush, concealer, foundation, face powder, sunscreen,
sun-tan lotion, self tanning compositions, bronzers, baby powder,
diaper rash products, deodorants and antiperspirants.
[0066] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in non-ingestible products as an
anticaking agent. By "anticaking agent" is meant a compound that
prevents solid compositions from forming large aggregates (i.e.,
clumps) and facilitates a consistent granular or powdered
composition. Exemplary non-ingestible products of the invention
employing the CO.sub.2 sequestering composition as an anticaking
agent include baby powder, foundation, face powder, blush,
eyeshadow, diaper rash products, concealer, laundry detergent,
dishwashing powder, rinse agents, fast-dry agents, room deodorizing
powders, bathroom cleaners and powdered bleach.
[0067] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in non-ingestible products as a
buffering agent. By "buffering agent" is meant a compound that
minimizes changes in pH. As such, the CO.sub.2 sequestering
component may act to buffer any acidic or basic components
traditionally used in formulations for these products or may be
used to maintain a suitable pH during its use. Exemplary
non-ingestible products of the invention employing the CO.sub.2
sequestering composition as a buffering agent include lip gloss,
nail polish, sunscreens, sun-tan lotion, baby wipes, acne
prevention wipes, acne treatment cream, facial cleansing soap and
exfoliating soap, antiperspirants, deodorants, aftershave lotion,
bath soap, bath wash, shaving cream, shaving gel, makeup removal,
moisturizers, anti-wrinkle creams, anti-drying lotions, anti-itch
cream, anti-fungal creams, conditioner, hair spray, hair gel,
mouse, hair colorants, depilatory treatments, hair bleach,
antiseptic sprays, antibacterial gels, laundry detergent, stain
remover, teeth whitening agents, dishwashing liquid, dishwashing
powders, dishwashing gels, rinse agents, fast-dry agents, bathroom
cleaners and all-purpose cleaners.
[0068] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in non-ingestible products as a
filler. By "filler" is meant a non-reactive, solid ingredient used
to dilute other solids, or to increase the volume of a product. In
some instances, the CO.sub.2 sequestering composition may be used
to dilute a potent active ingredient, which may be present in very
small amounts, so that the product can be handled more easily. In
other instances, the CO.sub.2 sequestering composition may be used
to increase the volume of an expensive ingredient without
disturbing the main function of the product. Exemplary
non-ingestible products of the invention employing the CO.sub.2
sequestering composition as a filler include baby powder,
foundation, face powder, blush, eyeshadow, diaper rash products,
concealer, laundry detergent, dishwashing powder, rinse agents,
fast-dry agents, room deodorizing powders, bathroom cleaners and
powdered bleach.
[0069] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in non-ingestible products as a
colorant. By "colorant" is meant a compound that is able to impart
a color to a product. Since the CO.sub.2 sequestering precipitate
of the invention is inherently white in color, it is able to
improve the white color of already white products, and lighten the
color of those products that are not white. Exemplary
non-ingestible products of the invention employing the CO.sub.2
sequestering composition as a filler include eyeshadow, blush,
concealer, foundation, face powder, sunscreens, sun-tan lotion,
self tanning compositions, bronzers, baby powder, acne treatment
cream, facial cleansing soap, exfoliating soap, antiperspirants,
deodorants, bath soap, bath wash, shaving cream, moisturizers,
anti-wrinkle cream, teeth whitening agents, lotions, anti-inch
cream, anti-fungal cream, toothpaste, shampoo, conditioner, hair
mousse, hair colorants, laundry detergent, dishwashing powders and
room deodorizing products.
[0070] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in non-ingestible products as an
opacifying agent. By "opacifying agent" is meant a substance that
reduces the clear or transparent appearance of a product. The
opacity of the non-ingestible product may vary depending on the
particle sizes of the CO.sub.2 sequestering composition. For
substantially opaque materials (e.g., anti-wrinkle cream), large
particle sizes may be used (.gtoreq.1 micron). For compositions
where a less substantial opacity is desired, small particles may be
used (.ltoreq.0.5 micron). Exemplary non-ingestible products of the
invention employing the CO.sub.2 sequestering composition as an
opacifying agent include anti-wrinkle cream, bronzer, sun-tan
lotion and self-tanning compositions.
[0071] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in non-ingestible products as an
oral-care agent. By "oral-care agent" is meant a compound that may
be used to polish teeth, reduce oral odor or otherwise cleanse or
deodorize the teeth and mouth. In addition to being a mild abrasive
for polishing teeth, the CO.sub.2 sequestering composition, when
incorporated in products used for oral hygiene, can buffer acids
that facilitate tooth decay and provide a whitening component to
oral-care products. Exemplary non-ingestible products of the
invention employing the CO.sub.2 sequestering composition as an
oral-care agent include toothpaste, teeth whitening agents and
mouthwash.
[0072] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in non-ingestible products as a
UV-scattering agent. By "UV-scattering agent" is meant a compound
that can sufficiently scatter UV light. Depending on the particle
sizes of the CO.sub.2 sequestering precipitate, the amount of UV
light (i.e., light having wavelengths.ltoreq.380 nm) that is
scattered and thus unavailable for absorption may vary. In some
instances, the amount of UV light scattered may be 10% or more,
including 25% or more, such as 50% or more. In some embodiments of
the invention, the CO.sub.2 sequestering composition may be the
only component used to protect against UV radiation. In other
embodiments, the CO.sub.2 sequestering composition may be used in
combination with conventional UV absorbing compositions to protect
against UV radiation. Exemplary non-ingestible products of the
invention employing the CO.sub.2 sequestering composition as a
UV-scattering agent include sunscreen, face powder, blush and
foundation.
Food, Vitamins, Nutritional Supplements, Pharmaceuticals and Other
Ingestible Products
[0073] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into ingestible
products. By "ingestible" is meant compositions that are taken
orally, even though they may not be digested, where ingestibles are
formulated for human consumption. Ingestibles of the invention may
include food products, vitamins, nutritional supplements,
pharmaceuticals and mineral fortified products.
[0074] Of interest are novel ingestible formulations which
incorporate the CO.sub.2 sequestering composition of the invention
into food products. Food products of the invention are any
ingestible solids or liquids, usually composed of carbohydrates,
fats, water and/or proteins that are consumed for nutrition or
pleasure. In certain embodiments, the CO.sub.2 sequestering
composition of the invention may be employed in food products as a
buffering agent, filler, anti-caking agent, colorant, emulsifier or
stabilizer. Traditional buffering agents, fillers, anti-caking
agents, colorants, emulsifiers and stabilizers conventionally found
in food products may be substituted entirely or a certain amount
removed and replaced by the CO.sub.2 sequestering compositions of
the present invention.
[0075] In some embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in food products as a buffering
agent. As described above, the CO.sub.2 sequestering composition
may act to minimize pH changes caused by any acidic or basic
components traditionally used in formulations for these products or
may be used to maintain a suitable pH for taste. Exemplary food
products of the invention employing the CO.sub.2 sequestering
composition as a buffering agent include condiments, fat emulsions
(e.g., salad dressings) water-based flavored drinks (e.g., energy
drinks, sports drinks, electrolyte drinks), soybean products (e.g.,
soy sauce), processed fruits, canned fruits, processed vegetables,
canned vegetables, processed meats, canned meats, beer, wine,
cider, malt beverages and canned soups.
[0076] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in food products as a filler. As
described above, a filler is a non-reactive, solid ingredient used
to dilute other solids, or to increase the volume of a product.
Exemplary food products of the invention employing the CO.sub.2
sequestering composition as a filler include seasonings,
dairy-based products, confectionary substances, baby food, baby
formula, sweeteners, milk powders, edible casings and milk
substitutes.
[0077] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in food products as an anti-caking
agent. As described above, an anti-caking agent is used to prevent
solid compositions from forming large aggregates (i.e., clumps) and
facilitates a consistent granular or powdered composition.
Exemplary food products of the invention employing the CO.sub.2
sequestering composition as an anti-caking agent include milk
powders, baby formula, confectionary substances, sweeteners and
seasonings.
[0078] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in food products as an emulsifier.
By "emulsifier" is meant a substance that forms or maintains a
uniform mixture of two or more immiscible phases. In some
instances, the CO.sub.2 sequestering composition can be used to
form a mixture of oil and water in food products. Exemplary food
products of the invention employing the CO.sub.2 sequestering
composition as an emulsifier include fat emulsions (e.g., salad
dressings), broths and condiments.
[0079] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in food products as a colorant. As
described above, a colorant is a compound that is able to impart a
color to a product. Since the CO.sub.2 sequestering precipitate of
the invention is inherently white in color, it is able to improve
the white color of already white products, and lighten the color of
those products that are not white. Exemplary food products of the
invention employing the CO.sub.2 sequestering composition as a
colorant include dairy based products, milk substitutes, milk
powder, sweeteners, seasonings, baby formula, dried egg products
and confectionary substances.
[0080] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be employed in food products as a stabilizer.
By "stabilizer" is meant a substance that facilitates a uniform
dispersion of two or more immiscible substances. Exemplary food
products of the invention employing the CO.sub.2 sequestering
composition as a stabilizer include dairy based products, canned
soups, milk substitutes, liquid whey and condiments.
[0081] Also of interest are novel ingestible formulations which
incorporate the CO.sub.2 sequestering composition of the invention
into vitamins, nutritional supplements and pharmaceuticals.
Vitamins, nutritional supplements and pharmaceuticals of the
invention may include any ingestible solids or liquids that are not
food products (as described above) consumed for nutritional or
medicinal purposes. In certain embodiments, the CO.sub.2
sequestering composition of the invention may be employed in
vitamins, nutritional supplements and pharmaceuticals as buffering
agents, fillers, anti-caking agents, colorants, and binders. By
"binder" is meant a substance that is used to hold together
ingredients of a compressed tablet or cake. Vitamins, nutritional
supplements and pharmaceuticals of the invention may be in the form
or a powder, syrup, liquid, tablet, capsule with powder filling,
liquid-gel capsule and the like. Vitamins, nutritional supplements
and pharmaceuticals may include, but are not limited to
over-the-counter medications, behind-the-counter medications,
prescription medications, liquid nutritional drinks, nutritional
powders, weight-loss supplements, multivitamins, nutraceuticals,
laxatives, antacids and the like. Traditional buffering agents,
fillers, anti-caking agents, colorants and binders conventionally
found in vitamins, nutritional supplements and pharmaceuticals may
be substituted entirely or a certain amount removed and replaced by
the CO.sub.2 sequestering compositions of the present
invention.
[0082] An exemplary embodiment, depending upon the components in
the water and the gaseous stream used to generate the carbonate
precipitate of the invention (as described in detail below) include
preparing the CO.sub.2 sequestering carbonate precipitate in tablet
form for use as a dietary supplement or as an antacid (e.g.,
calcium supplement). Substantially pure calcium and magnesium
carbonate precipitate provided by methods of the invention may be
further processed into tablets by any convenient protocol. The
CO.sub.2 sequestering carbonate precipitate may also be
incorporated into tablets containing multiple dietary supplements
(e.g., multivitamin).
[0083] In another exemplary embodiment, the CO.sub.2 sequestering
composition of invention may be used for the mineral fortification
of food products. By "mineral fortification" is meant the addition
of minerals (e.g., calcium, magnesium) to food during production or
processing. Food products of the invention may be fortified with
minerals by substantially pure CO.sub.2 sequestering carbonate
precipitate using any convenient protocol, such as for example
mixing the CO.sub.2 sequestering composition with the food
product.
[0084] Depending on the type of food product, the amount of
CO.sub.2 sequestering composition added may vary, ranging from 5 mg
to 1500 mg, such as 10 mg to 500 mg and including 100 mg to 200 mg.
Exemplary food products that may be fortified with CO.sub.2
sequestering compositions of the invention include, but are not
limited to: baked goods (e.g., breads, cookies, biscuits, crackers,
waffles, pancakes, cakes); bars (e.g., baked bars, breakfast bars,
granola bars, energy bars); beverages (e.g., opaque beverages, both
dairy and non-dairy); breakfast cereals; chewing gum; candies
(e.g., opaque hard candies, chocolate, nougats, caramels, cream
filled); frozen desserts (e.g., ice cream, frozen soy desserts,
frozen yogurts); infant formulas; ingredient enrichment (e.g.,
flour, meals, grains, wheat, corn, rice, oats); liquid meals (e.g.,
replacement meals, special formulations for diabetic, diet or
slimming drinks); milks; pastas (e.g., macaroni, spaghetti,
noodles, couscous, ramen, instant noodles); powdered drink mixes
(e.g., flavored milks, energy drinks, protein drinks); probiotics;
soymilks; tofu; yogurts (e.g., bulk-fermented yogurts, drinkable
yogurts, yogurt-based smoothies).
Animal Ingestible Products
[0085] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into animal
ingestible products. By "animal ingestible" is meant compositions
that are taken orally and are formulated for non-human (e.g.,
livestock, pets) consumption Animal Ingestible products of the
invention may include but are not limited to animal food products,
vitamins, nutritional supplements and pharmaceuticals for animal
consumption. Of interest are novel animal-ingestible product
formulations which employ the CO.sub.2 sequestering composition of
the invention as buffering agents, fillers, anti-caking agents,
colorants, emulsifiers, stabilizers and binders into food products,
vitamins, nutritional supplements and pharmaceuticals formulated
for animal consumption. Traditional buffering agents, fillers,
anti-caking agents, colorants, emulsifiers, stabilizers and binders
conventionally found in animal-ingestible products may be
substituted entirely or a certain amount removed and replaced by
the CO.sub.2 sequestering compositions of the present
invention.
Agricultural Products
[0086] The present invention also includes novel formulations which
incorporate the CO.sub.2 sequestering composition into agricultural
products. By "agricultural products" is meant any composition that
is employed in cultivating land, raising crops or vegetation,
farming, and feeding, breeding, and raising livestock or any other
activity associated therewith. Agricultural products of the
invention may be soil amendment compositions (e.g., fertilizer,
remediation), pest control (fungicides, insecticides) or
nutritional and/or medicinal ingestible compositions for livestock
(as detailed above). The CO.sub.2 sequestering composition of the
invention may be added to traditional agricultural products as a
supplement or entirely replace conventionally used agricultural
products.
[0087] In some embodiments, the CO.sub.2 sequestering composition
of the invention is a soil amendment. By "soil amendment" is meant
a composition that aims to improve or remediate the desired
properties of soil for agricultural usage. In some instances the
soil amendment is a fertilizer to supply nutrients (e.g., calcium,
magnesium) to the soil. In other instances, the soil amendment is a
buffering agent to reduce changes to the pH of the soil. The
CO.sub.2 sequestering composition of the invention may be contacted
with the soil in the form of a slurry or a powder. The CO.sub.2
sequestering precipitate is either mixed with water prior to being
dispensed onto the surface of the soil or is dispensed as a dry
powder. Contacting the composition with the soil may be achieved
using any convenient protocol. It may be gravity fed or pumped
through hoses, spray nozzles or fixed sprayers to uniformly apply
the composition. In other instances, the CO.sub.2 soil
stabilization compositions of the invention may be poured from a
reservoir or applied manually without the use of any industrial
machinery. The composition may also be applied by releasing the
composition at a depth within the soil by pumping the composition
beneath the surface of the soil to be treated or by digging to a
depth in the soil using conventional digging machinery and further
applying the composition. The composition is then mixed into the
soil. In any of the various treatments within the scope of the
present invention, the soil may be mixed in situ or may be
temporarily removed from the ground for mixing and then replaced.
Mixing the soil with the CO.sub.2 sequestering composition may be
accomplished using any convenient mixing equipment (e.g., rotary
mixers, cement mixers, etc.). The prepared CO.sub.2-sequestering
composition and soil mixture is then rotated and the entire mixture
is blended in a uniform manner.
[0088] In other embodiments, the CO.sub.2 sequestering composition
of the invention may be incorporated into pesticides. The term
"pesticide" is used in its conventional sense to mean any compound
that is used to eliminate, control or inhibit the proliferation of
any organism which has characteristics that are regarded as
injurious or unwanted. Pesticides of the invention may include
those formulations used against insects, fungi, bacteria, rodents
and the like. The CO.sub.2 sequestering composition may be employed
in pesticides to improve the pesticide action or to aid in the
application of the pesticide. For example, the CO.sub.2
sequestering composition may be employed as a water absorbent or as
a granulating agent. In other instances, the composition may be
employed as a crop-dusting filler to facilitate the uniform
distribution of the pesticide on vegetation or crops. Pesticides of
the invention may be prepared using any conventional protocol with
the exception that an amount of the CO.sub.2 sequestering
composition is added. The amount of CO.sub.2 sequestering additive
in the pesticide may vary, and may be 1% by weight or more, such as
3% by weight or more, including 5% by weight or more, such as 25%
by weight or more. The CO.sub.2 sequestrating composition may be
incorporated into the pesticides during the formulation of the
pesticide or may be subsequently added to the finished pesticide
product. Incorporation of the composition into the pesticide may be
accomplished by mixing the composition with the pesticide and
rotating the mixture under agitation, vortex or sonication and
blending into a uniform pesticide product.
Environmental Remediation
[0089] The CO.sub.2 sequestering composition of the invention may
also be employed in environmental remediation. By "environmental
remediation" is meant the removal of pollution or contaminants from
environmental media such as soil, groundwater, sediment or water
for the general protection of human health and the environment.
[0090] In some embodiments, environmental remediation employing the
CO.sub.2 sequestering composition of the invention is forest soil
restoration. The application of the CO.sub.2 sequestering
composition may be employed in forest soil restoration for
neutralizing acidic soil, improving the calcium and magnesium
content in soil, increasing the biological activity of organically
influenced soil horizons, intensifying the nitrification process in
the soil or stabilizing metal organic complexes in order to
decrease or prevent heavy-metal pollution. The CO.sub.2
sequestering composition of the invention may be contacted with the
forest soil using any convenient protocol (as discussed above). It
may be applied using devices that are gravity fed or it can be
pumped through hoses, spray nozzles or fixed sprayers. The
composition may also be poured from a reservoir or applied manually
without the use of any industrial machinery. In some instances, the
CO.sub.2 sequestering composition may be dispensed from a
helicopter or crop-dusting airplane.
[0091] In other embodiments, environmental remediation employing
the CO.sub.2 sequestering composition of the invention is the
neutralization of over-acidified water. By "acidified water" is
meant a large body of water (e.g., pond, lake) that has a pH below
6.5 under ambient conditions and is often lower, such as 6.0 and
including 5.0. The CO.sub.2 sequestering composition can be applied
by any convenient protocol. In some instances, the composition is
applied as a slurry or as a finely ground powder. Slurries are
typically sprayed onto the water surface from boats or from
stations located on the water, whereas powder is dispensed by
helicopter or fixed-wing planes. The application of the CO.sub.2
sequestering composition may cause increases in pH that vary
ranging from 1 to 4, including 2 to 4, such as 2.5 to 3.5. The
amount of the CO.sub.2 sequestering composition applied to the
acidified water may vary considerably (depending on the size and
location of the body of water and the pH of the water) ranging from
0.1 kg to 100 kg or more, such as 1000 kg or more, including 10,000
kg or more.
Preparation of CO.sub.2 Sequestering Compositions
[0092] Aspects of the invention also include methods of preparing
CO.sub.2 sequestering compositions. CO.sub.2 sequestering
compositions may be prepared by producing a CO.sub.2 sequestering
additive, e.g., as described above, and then preparing the
composition from the component. Each of these aspects of the
invention will now be described in greater detail.
[0093] A variety of different methods may be employed to prepare
the CO.sub.2 sequestering additive of the compositions of the
invention. CO.sub.2 sequestration protocols of interest include,
but are not limited to, those disclosed in U.S. patent application
Ser. Nos. 12/126,776, titled, "Hydraulic cements comprising
carbonate compound compositions," filed 23 May 2008; 12/163,205,
titled "DESALINATION METHODS AND SYSTEMS THAT INCLUDE CARBONATE
COMPOUND PRECIPITATION," filed 27 Jun. 2008; and 12/486,692, titled
"METHODS AND SYSTEMS FOR UTILIZING WASTE SOURCES OF METAL OXIDES"
filed 17 Jun. 2009; 12/501,217, titled "PRODUCTION OF
CARBONATE-CONTAINING COMPOSITIONS FROM MATERIAL COMPRISING METAL
SILICATE," filed 10 Jul. 2009; and 12/557,492, titled "CO2
COMMODITY TRADING SYSTEM AND METHOD," filed 10 Sep. 2009; as well
as International Application No. PCT/US08/88318, titled, "METHODS
OF SEQUESTERING CO.sub.2," filed 24 Dec. 2008; and PCT/US09/45722,
titled "ROCK AND AGGREGATE, AND METHODS OF MAKING AND USING THE
SAME," filed 29 May 2009; as well as pending U.S. Provisional
Patent Application Ser. Nos. 61/081,299; 61/082,766; 61/088,347;
61/088,340; and 61/101,631; the disclosures of which are herein
incorporated by reference.
[0094] CO.sub.2 sequestering additives of the invention include
carbonate compositions that may be produced by precipitating a
calcium and/or magnesium carbonate composition from a water. The
carbonate compound compositions that make up the CO.sub.2
sequestering additives of the invention include may metastable
carbonate compounds that may be precipitated from a water, such as
a salt-water, as described in greater detail below. The carbonate
compound compositions of the invention include precipitated
crystalline and/or amorphous carbonate compounds.
[0095] In certain embodiments, the water from which the carbonate
precipitates are produced is a saltwater. In such embodiments, the
carbonate compound composition may be viewed as a saltwater derived
carbonate compound composition. As used herein, "saltwater-derived
carbonate compound composition" means a composition derived from
saltwater and made up of one or more different carbonate
crystalline and/or amorphous compounds with or without one or more
hydroxide crystalline or amorphous compounds. The term "saltwater"
is employed in its conventional sense to refer to a number of
different types of aqueous liquids other than fresh water, where
the term "saltwater" includes brackish water, sea water and brine
(including man-made brines, e.g., geothermal plant wastewaters,
desalination waste waters, etc), as well as other salines having a
salinity that is greater than that of freshwater. Brine is water
saturated or nearly saturated with salt and has a salinity that is
50 ppt (parts per thousand) or greater. Brackish water is water
that is saltier than fresh water, but not as salty as seawater,
having a salinity ranging from 0.5 to 35 ppt. Seawater is water
from a sea or ocean and has a salinity ranging from 35 to 50 ppt.
The saltwater source from which the mineral composition of the
cements of the invention is derived may be a naturally occurring
source, such as a sea, ocean, lake, swamp, estuary, lagoon, etc.,
or a man-made source. In certain embodiments, the saltwater source
of the mineral composition is seawater.
[0096] While the present invention is described primarily in terms
of saltwater sources, in certain embodiments, the water employed in
the invention may be a mineral rich, e.g., calcium and/or magnesium
rich, freshwater source. The water employed in the process is one
that includes one or more alkaline earth metals, e.g., magnesium,
calcium, etc, and is another type of
alkaline-earth-metal-containing water that finds use in embodiments
of the invention. Waters of interest include those that include
calcium in amounts ranging from 50 to 20,000 ppm, such as 100 to
10,0000 ppm and including 200 to 5000 ppm. Waters of interest
include those that include magnesium in amounts ranging from 50 to
20,000 ppm, such as 200 to 10000 ppm and including 500 to 5000
ppm.
[0097] The saltwater-derived carbonate compound compositions of
embodiments of the cements are ones that are derived from a
saltwater. As such, they are compositions that are obtained from a
saltwater in some manner, e.g., by treating a volume of a saltwater
in a manner sufficient to produce the desired carbonate compound
composition from the initial volume of saltwater. The carbonate
compound compositions of certain embodiments are produced by
precipitation from a water, e.g., a saltwater, a water that
includes alkaline earth metals, such as calcium and magnesium,
etc., where such waters are collectively referred to as
alkaline-earth-metal-containing waters.
[0098] The saltwater employed in methods may vary. As reviewed
above, saltwaters of interest include brackish water, sea water and
brine, as well as other salines having a salinity that is greater
than that of freshwater (which has a salinity of less than 5 ppt
dissolved salts. In some embodiments, calcium rich waters may be
combined with magnesium silicate minerals, such as olivine or
serpentine, in solution that has become acidic due to the addition
on carbon dioxide to form carbonic acid, which dissolves the
magnesium silicate, leading to the formation of calcium magnesium
silicate carbonate compounds as mentioned above.
[0099] In methods of producing the carbonate compound compositions
of the aggregates of the invention, a volume of water is subjected
to carbonate compound precipitation conditions sufficient to
produce a precipitated carbonate compound composition and a mother
liquor (i.e., the part of the water that is left over after
precipitation of the carbonate compound(s) from the saltwater). The
resultant precipitates and mother liquor collectively make up the
carbonate compound compositions of the invention. Any convenient
precipitation conditions may be employed, which conditions result
in the production of a carbonate compound composition sequestration
product.
[0100] Precipitation conditions of interest may vary. For example,
the temperature of the water may be within a suitable range for the
precipitation of the desired mineral to occur. In some embodiments,
the temperature of the water may be in a range from 5 to 70.degree.
C., such as from 20 to 50.degree. C. and including from 25 to
45.degree. C. As such, while a given set of precipitation
conditions may have a temperature ranging from 0 to 100.degree. C.,
the temperature of the water may have to be adjusted in certain
embodiments to produce the desired precipitate.
[0101] In normal sea water, 93% of the dissolved CO.sub.2 is in the
form of bicarbonate ions (HCO.sub.3.sup.-) and 6% is in the form of
carbonate ions (CO.sub.3.sup.-2). When calcium carbonate
precipitates from normal sea water, CO.sub.2 is released. In fresh
water, above pH 10.33, greater than 90% of the carbonate is in the
form of carbonate ion, and no CO.sub.2 is released during the
precipitation of calcium carbonate. In sea water this transition
occurs at a slightly lower pH, closer to a pH of 9.7. While the pH
of the water employed in methods may range from 5 to 14 during a
given precipitation process, in certain embodiments the pH is
raised to alkaline levels in order to drive the precipitation of
carbonate compounds, as well as other compounds, e.g., hydroxide
compounds, as desired. In certain of these embodiments, the pH is
raised to a level which minimizes if not eliminates CO.sub.2
production during precipitation, causing dissolved CO.sub.2, e.g.,
in the form of carbonate and bicarbonate, to be trapped in the
carbonate compound precipitate. In these embodiments, the pH may be
raised to 10 or higher, such as 11 or higher.
[0102] The pH of the water may be raised using any convenient
approach. In certain embodiments, a pH raising agent may be
employed, where examples of such agents include oxides, hydroxides
(e.g., calcium oxide in fly ash, potassium hydroxide, sodium
hydroxide, brucite (Mg(OH.sub.2), etc.), carbonates (e.g., sodium
carbonate) and the like. One such approach is to use the coal ash
from a coal-fired power plant, which contains many oxides, to
elevate the pH of the water. Other coal processes, like the
gasification of coal, to produce syngas, also produce hydrogen gas
and carbon monoxide, and may serve as a source of hydroxide as
well. Some naturally occurring minerals, such as serpentine,
contain hydroxide, and can be dissolved, yielding a hydroxide
source. The addition of serpentine, also releases silica and
magnesium into the solution, leading to the formation of silica
containing carbonate compounds. The amount of pH elevating agent
that is added to the water will depend on the particular nature of
the agent and the volume of water being modified, and will be
sufficient to raise the pH of the water to the desired value.
Alternatively, the pH of the water source can be raised to the
desired level by electrolysis of water. Where electrolysis is
employed, a variety of different protocols may be taken, such as
use of the Mercury cell process (also called the Castner-Kellner
process); the Diaphragm cell process and the membrane cell process.
Where desired, byproducts of the hydrolysis product, e.g., H.sub.2,
sodium metal, etc. may be harvested and employed for other
purposes, as desired. In some embodiments, described further below,
HCl is a byproduct of the process and may be used, e.g. in the
manufacture of poly (vinyl chloride) (PVC).
[0103] Methods of the invention include contacting a volume of an
aqueous solution of divalent cations with a source of CO.sub.2 (to
dissolve CO.sub.2) and subjecting the resultant solution to
precipitation conditions. In some embodiments, a volume of an
aqueous solution of divalent cations is contacted with a source of
CO.sub.2 (to dissolve CO.sub.2) while subjecting the aqueous
solution to precipitation conditions. The dissolution of CO.sub.2
into the aqueous solution of divalent cations produces carbonic
acid, a species in equilibrium with both bicarbonate and carbonate.
In order to produce carbonate-containing precipitation material,
protons are removed from various species (e.g. carbonic acid,
bicarbonate, hydronium, etc.) in the divalent cation-containing
solution to shift the equilibrium toward carbonate. As protons are
removed, more CO.sub.2 goes into solution. In some embodiments,
proton-removing agents and/or methods are used while contacting a
divalent cation-containing aqueous solution with CO.sub.2 to
increase CO.sub.2 absorption in one phase of the precipitation
reaction, wherein the pH may remain constant, increase, or even
decrease, followed by a rapid removal of protons (e.g., by addition
of a base) to cause rapid precipitation of carbonate-containing
precipitation material. Protons may be removed from the various
species (e.g. carbonic acid, bicarbonate, hydronium, etc.) by any
convenient approach, including, but not limited to use of naturally
occurring proton-removing agents, use of microorganisms and fungi,
use of synthetic chemical proton-removing agents, recovery of
man-made waste streams, and using electrochemical means.
[0104] Naturally occurring proton-removing agents encompass any
proton-removing agents that can be found in the wider environment
that may create or have a basic local environment. Some embodiments
provide for naturally occurring proton-removing agents including
minerals that create basic environments upon addition to solution.
Such minerals include, but are not limited to, lime (CaO);
periclase (MgO); iron hydroxide minerals (e.g., goethite and
limonite); and volcanic ash. Methods for digestion of such minerals
and rocks comprising such minerals are provided herein. Some
embodiments provide for using naturally alkaline bodies of water as
naturally occurring proton-removing agents. Examples of naturally
alkaline bodies of water include, but are not limited to surface
water sources (e.g. alkaline lakes such as Mono Lake in California)
and ground water sources (e.g. basic aquifers such as the deep
geologic alkaline aquifers located at Searles Lake in California).
Other embodiments provide for use of deposits from dried alkaline
bodies of water such as the crust along Lake Natron in Africa's
Great Rift Valley. In some embodiments, organisms that excrete
basic molecules or solutions in their normal metabolism are used as
proton-removing agents. Examples of such organisms are fungi that
produce alkaline protease (e.g., the deep-sea fungus Aspergillus
ustus with an optimal pH of 9) and bacteria that create alkaline
molecules (e.g., cyanobacteria such as Lyngbya sp. from the Atlin
wetland in British Columbia, which increases pH from a byproduct of
photosynthesis). In some embodiments, organisms are used to produce
proton-removing agents, wherein the organisms (e.g., Bacillus
pasteurii, which hydrolyzes urea to ammonia) metabolize a
contaminant (e.g. urea) to produce proton-removing agents or
solutions comprising proton-removing agents (e.g., ammonia,
ammonium hydroxide). In some embodiments, organisms are cultured
separately from the precipitation reaction mixture, wherein
proton-removing agents or solution comprising proton-removing
agents are used for addition to the precipitation reaction mixture.
In some embodiments, naturally occurring or manufactured enzymes
are used in combination with proton-removing agents to invoke
precipitation of precipitation material. Carbonic anhydrase, which
is an enzyme produced by plants and animals, accelerates
transformation of carbonic acid to bicarbonate in aqueous
solution.
[0105] Chemical agents for effecting proton removal generally refer
to synthetic chemical agents that are produced in large quantities
and are commercially available. For example, chemical agents for
removing protons include, but are not limited to, hydroxides,
organic bases, super bases, oxides, ammonia, and carbonates.
Hydroxides include chemical species that provide hydroxide anions
in solution, including, for example, sodium hydroxide (NaOH),
potassium hydroxide (KOH), calcium hydroxide (Ca(OH).sub.2), or
magnesium hydroxide (Mg(OH).sub.2). Organic bases are
carbon-containing molecules that are generally nitrogenous bases
including primary amines such as methyl amine, secondary amines
such as diisopropylamine, tertiary such as diisopropylethylamine,
aromatic amines such as aniline, heteroaromatics such as pyridine,
imidazole, and benzimidazole, and various forms thereof. In some
embodiments, an organic base selected from pyridine, methylamine,
imidazole, benzimidazole, histidine, and a phophazene is used to
remove protons from various species (e.g., carbonic acid,
bicarbonate, hydronium, etc.) for precipitation of precipitation
material. In some embodiments, ammonia is used to raise pH to a
level sufficient to precipitate precipitation material from a
solution of divalent cations and an industrial waste stream. Super
bases suitable for use as proton-removing agents include sodium
ethoxide, sodium amide (NaNH.sub.2), sodium hydride (NaH), butyl
lithium, lithium diisopropylamide, lithium diethylamide, and
lithium bis(trimethylsilyl)amide. Oxides including, for example,
calcium oxide (CaO), magnesium oxide (MgO), strontium oxide (SrO),
beryllium oxide (BeO), and barium oxide (BaO) are also suitable
proton-removing agents that may be used. Carbonates for use in the
invention include, but are not limited to, sodium carbonate.
[0106] In addition to comprising cations of interest and other
suitable metal forms, waste streams from various industrial
processes may provide proton-removing agents. Such waste streams
include, but are not limited to, mining wastes; fossil fuel burning
ash (e.g., combustion ash such as fly ash, bottom ash, boiler
slag); slag (e.g. iron slag, phosphorous slag); cement kiln waste;
oil refinery/petrochemical refinery waste (e.g. oil field and
methane seam brines); coal seam wastes (e.g. gas production brines
and coal seam brine); paper processing waste; water softening waste
brine (e.g., ion exchange effluent); silicon processing wastes;
agricultural waste; metal finishing waste; high pH textile waste;
and caustic sludge. Mining wastes include any wastes from the
extraction of metal or another precious or useful mineral from the
earth. In some embodiments, wastes from mining are used to modify
pH, wherein the waste is selected from red mud from the Bayer
aluminum extraction process; waste from magnesium extraction from
sea water (e.g., Mg(OH).sub.2 such as that found in Moss Landing,
Calif.); and wastes from mining processes involving leaching. For
example, red mud may be used to modify pH as described in U.S.
Provisional Patent Application No. 61/161,369, titled,
"NEUTRALIZING INDUSTRIAL WASTES UTILIZING CO.sub.2 AND A DIVALENT
CATION SOLUTION", filed 18 Mar. 2009, which is hereby incorporated
by reference in its entirety. Fossil fuel burning ash, cement kiln
dust, and slag, collectively waste sources of metal oxides, further
described in U.S. patent application Ser. No. 12/486,692, titled,
"METHODS AND SYSTEMS FOR UTILIZING WASTE SOURCES OF METAL OXIDES,"
filed 17 Jun. 2009, the disclosure of which is incorporated herein
in its entirety, may be used in alone or in combination with other
proton-removing agents to provide proton-removing agents for the
invention. Agricultural waste, either through animal waste or
excessive fertilizer use, may contain potassium hydroxide (KOH) or
ammonia (NH.sub.3) or both. As such, agricultural waste may be used
in some embodiments of the invention as a proton-removing agent.
This agricultural waste is often collected in ponds, but it may
also percolate down into aquifers, where it can be accessed and
used.
[0107] Electrochemical methods are another means to remove protons
from various species in a solution, either by removing protons from
solute (e.g., deprotonation of carbonic acid or bicarbonate) or
from solvent (e.g., deprotonation of hydronium or water).
Deprotonation of solvent may result, for example, if proton
production from CO.sub.2 dissolution matches or exceeds
electrochemical proton removal from solute molecules. In some
embodiments, low-voltage electrochemical methods are used to remove
protons, for example, as CO.sub.2 is dissolved in the precipitation
reaction mixture or a precursor solution to the precipitation
reaction mixture (i.e., a solution that may or may not contain
divalent cations). In some embodiments, CO.sub.2 dissolved in an
aqueous solution that does not contain divalent cations is treated
by a low-voltage electrochemical method to remove protons from
carbonic acid, bicarbonate, hydronium, or any species or
combination thereof resulting from the dissolution of CO.sub.2. A
low-voltage electrochemical method operates at an average voltage
of 2, 1.9, 1.8, 1.7, or 1.6 V or less, such as 1.5, 1.4, 1.3, 1.2,
1.1 V or less, such as 1 V or less, such as 0.9 V or less, 0.8 V or
less, 0.7 V or less, 0.6 V or less, 0.5 V or less, 0.4 V or less,
0.3 V or less, 0.2 V or less, or 0.1 V or less. Low-voltage
electrochemical methods that do not generate chlorine gas are
convenient for use in systems and methods of the invention.
Low-voltage electrochemical methods to remove protons that do not
generate oxygen gas are also convenient for use in systems and
methods of the invention. In some embodiments, low-voltage
electrochemical methods generate hydrogen gas at the cathode and
transport it to the anode where the hydrogen gas is converted to
protons. Electrochemical methods that do not generate hydrogen gas
may also be convenient. In some embodiments, electrochemical
processes to remove protons do not generate a gas at the anode. In
some instances, electrochemical methods to remove protons do not
generate any gaseous by-byproduct. Electrochemical methods for
effecting proton removal are further described in U.S. patent
application Ser. No. 12/344,019, titled, "METHODS OF SEQUESTERING
CO.sub.2," filed 24 Dec. 2008; U.S. patent application Ser. No.
12/375,632, titled, "LOW ENERGY ELECTROCHEMICAL HYDROXIDE SYSTEM
AND METHOD," filed 23 Dec. 2008; International Patent Application
No. PCT/US08/088,242, titled, "LOW ENERGY ELECTROMECHANICAL
HYDROXIDE SYSTEM AND METHOD," filed 23 Dec. 2008; International
Patent Application No. PCT/US09/32301, titled, "LOW-ENERGY
ELECTROCHEMICAL BICARBONATE ION SOLUTION," filed 28 Jan. 2009; and
International Patent Application No. PCT/US09/48511, titled,
"LOW-ENERGY 4-CELL ELECTROCHEMICAL SYSTEM WITH CARBON DIOXIDE GAS,"
filed 24 Jun. 2009, each of which are incorporated herein by
reference in their entirety.
[0108] Low voltage electrochemical processes may produce hydroxide
at the cathode and protons at the anode; where such processes
utilize a salt containing chloride, e.g. NaCl, a product of the
process will be HCl. In some embodiments of the invention, the HCL
from a low-voltage electrochemical process as described herein may
be used to make poly(vinyl chloride) (PVC). HCl from a low-voltage
electrochemical process, e.g. a process that operates at a voltage
of less than 2.0V, or less than 1.5V, or less than 1.0V, may be
used in reactions well-known in the art to produce a vinyl chloride
monomer. The vinyl chloride monomer may be used to produce
poly(vinyl chloride) in some embodiments. In further embodiments,
the PVC can be mixed with a carbonate precipitate formed by the
methods described herein, e.g. a slightly wet carbonate
precipitate, to form a building material. In some embodiments, the
PVC/carbonate mixture may be extruded to form a slightly foamed
profile, such as, e.g. a 2.times.4 or other lumber material.
Carbonate/PVC lumber formed by such methods are thus encompassed by
the invention. Such 1 umber may be CO.sub.2-sequestering because
the carbonate in the lumber is a CO.sub.2-sequestering additive. In
some embodiments, the amount of CO.sub.2 sequestering additive in
the formed element comprising PVC is 5 wt % or more. In some
embodiments, the amount of CO.sub.2 sequestering additive in the
formed element comprising PVC is 10 wt % or more, 15 wt % or more,
20 wt % or more, 25 wt % or more, 30 wt % or more, 35 wt % or more,
such as 40 wt % or more, 45 wt % or more, 50 wt %, 55 wt % or more,
60 wt % or more, such as up to 65 wt % or more. In some
embodiments, the amount of CO.sub.2 sequestering additive in the
formed element comprising PVC is 60 wt % or more. In some
embodiments, the PVC and CO.sub.2 sequestering additive are mixed
and formed in a screw extruder. In some embodiments, the formed
element is injection molded. In some embodiments, the PVC is foamed
to create a cellular structure that will hold anchoring devices
such as nails and screws. In some embodiments, the formed element
comprising PVC and CO.sub.2 sequestering additive is used to
fabricate building elements that are flame resistant. In some
embodiments, the formed element comprising PVC and CO.sub.2
sequestering additive is such that the amount of CO.sub.2
sequestering additive increases the finishability, i.e. ease of
cutting and sanding, of the formed element. In some embodiments,
the formed element comprising PVC and CO.sub.2 sequestering
additive is such that the amount of CO.sub.2 sequestering additive
enhances the coloring or appearance of the formed element. In some
embodiments, the formed element comprising PVC and CO.sub.2
sequestering additive is such that the amount of CO.sub.2
sequestering additive gives stiffness to the formed element. In
some embodiments, the CO.sub.2 sequestering additive is added to
the PVC during the production of the PVC. In some such embodiments,
the PVC can be derived from the CO.sub.2 sequestering methods of
the invention.
[0109] Alternatively, electrochemical methods may be used to
produce caustic molecules (e.g., hydroxide) through, for example,
the chlor-alkali process, or modification thereof. Electrodes
(i.e., cathodes and anodes) may be present in the apparatus
containing the divalent cation-containing aqueous solution or
gaseous waste stream-charged (e.g., CO.sub.2-charged) solution, and
a selective barrier, such as a membrane, may separate the
electrodes. Electrochemical systems and methods for removing
protons may produce by-products (e.g., hydrogen) that may be
harvested and used for other purposes. Additional electrochemical
approaches that may be used in systems and methods of the invention
include, but are not limited to, those described in U.S. patent
application Ser. No. 12/503,557, titled, "CO.sub.2 UTILIZATION IN
ELECTROCHEMICAL SYSTEMS," filed 15 Jul. 2009 and U.S. Provisional
Application No. 61/091,729, titled, "LOW ENERGY ABSORPTION OF
HYDROGEN ION FROM AN ELECTROLYTE SOLUTION INTO A SOLID MATERIAL,"
filed 11 Sep. 2008, the disclosures of which are herein
incorporated by reference.
[0110] Combinations of the above mentioned sources of proton
removal may be employed. One such combination is the use of a
microorganisms and electrochemical systems. Combinations of
microorganisms and electrochemical systems include microbial
electrolysis cells, including microbial fuel cells, and
bio-electrochemically assisted microbial reactors. In such
microbial electrochemical systems, microorganisms (e.g. bacteria)
are grown on or very near an electrode and in the course of the
metabolism of material (e.g. organic material) electrons are
generated that are taken up by the electrode.
[0111] Additives other than pH elevating agents may also be
introduced into the water in order to influence the nature of the
precipitate that is produced. As such, certain embodiments of the
methods include providing an additive in water before or during the
time when the water is subjected to the precipitation conditions.
Certain calcium carbonate polymorphs can be favored by trace
amounts of certain additives. For example, vaterite, a highly
unstable polymorph of CaCO.sub.3 which precipitates in a variety of
different morphologies and converts rapidly to calcite, can be
obtained at very high yields by including trace amounts of
lanthanum as lanthanum chloride in a supersaturated solution of
calcium carbonate. Other additives beside lanthanum that are of
interest include, but are not limited to transition metals and the
like. For instance, the addition of ferrous or ferric iron is known
to favor the formation of disordered dolomite (protodolomite) where
it would not form otherwise.
[0112] The nature of the precipitate can also be influenced by
selection of appropriate major ion ratios. Major ion ratios also
have considerable influence of polymorph formation. For example, as
the magnesium:calcium ratio in the water increases, aragonite
becomes the favored polymorph of calcium carbonate over
low-magnesium calcite. At low magnesium:calcium ratios,
low-magnesium calcite is the preferred polymorph. As such, a wide
range of magnesium:calcium ratios can be employed, including, e.g.,
100/1, 50/1, 20/1, 10/1, 5/1, 2/1, 1/1, 1/2, 1/5, 1/10, 1/20, 1/50,
1/100. In certain embodiments, the magnesium:calcium ratio is
determined by the source of water employed in the precipitation
process (e.g., seawater, brine, brackish water, fresh water),
whereas in other embodiments, the magnesium:calcium ratio is
adjusted to fall within a certain range.
[0113] Rate of precipitation also has a large effect on compound
phase formation. The most rapid precipitation can be achieved by
seeding the solution with a desired phase. Without seeding, rapid
precipitation can be achieved by rapidly increasing the pH of the
sea water, which results in more amorphous constituents. When
silica is present, the more rapid the reaction rate, the more
silica is incorporated with the carbonate precipitate. The higher
the pH is, the more rapid the precipitation is and the more
amorphous the precipitate is.
[0114] Accordingly, a set of precipitation conditions to produce a
desired precipitate from a water include, in certain embodiments,
the water's temperature and pH, and in some instances the
concentrations of additives and ionic species in the water.
Precipitation conditions may also include factors such as mixing
rate, forms of agitation such as ultrasonics, and the presence of
seed crystals, catalysts, membranes, or substrates. In some
embodiments, precipitation conditions include supersaturated
conditions, temperature, pH, and/or concentration gradients, or
cycling or changing any of these parameters. The protocols employed
to prepare carbonate compound precipitates according to the
invention may be batch or continuous protocols. It will be
appreciated that precipitation conditions may be different to
produce a given precipitate in a continuous flow system compared to
a batch system.
[0115] In certain embodiments, the methods further include
contacting the volume of water that is subjected to the mineral
precipitation conditions with a source of CO.sub.2. Contact of the
water with the source CO.sub.2 may occur before and/or during the
time when the water is subjected to CO.sub.2 precipitation
conditions. Accordingly, embodiments of the invention include
methods in which the volume of water is contacted with a source of
CO.sub.2 prior to subjecting the volume of saltwater to mineral
precipitation conditions. Embodiments of the invention include
methods in which the volume of salt water is contacted with a
source of CO.sub.2 while the volume of saltwater is being subjected
to carbonate compound precipitation conditions. Embodiments of the
invention include methods in which the volume of water is contacted
with a source of a CO.sub.2 both prior to subjecting the volume of
saltwater to carbonate compound precipitation conditions and while
the volume of saltwater is being subjected to carbonate compound
precipitation conditions. In some embodiments, the same water may
be cycled more than once, wherein a first cycle of precipitation
removes primarily calcium carbonate and magnesium carbonate
minerals, and leaves remaining alkaline water to which other
alkaline earth ion sources may be added, that can have more carbon
dioxide cycled through it, precipitating more carbonate
compounds.
[0116] The source of CO.sub.2 that is contacted with the volume of
saltwater in these embodiments may be any convenient CO.sub.2
source. The CO.sub.2 source may be a liquid, solid (e.g., dry ice)
or gaseous CO.sub.2 source. In certain embodiments, the CO.sub.2
source is a gaseous CO.sub.2 source. This gaseous CO.sub.2 is, in
certain instances, a waste feed from an industrial plant. The
nature of the industrial plant may vary in these embodiments, where
industrial plants of interest include power plants (e.g., as
described in further detail in International Application No.
PCT/US08/88318, titled, "METHODS OF SEQUESTERING CO.sub.2," filed
24 Dec. 2008, the disclosure of which is herein incorporated by
reference), chemical processing plants, steel mills, paper mills,
cement plants (e.g., as described in further detail in U.S.
Provisional Application Ser. No. 61/088,340, the disclosure of
which is herein incorporated by reference), and other industrial
plants that produce CO.sub.2 as a byproduct. By waste feed is meant
a stream of gas (or analogous stream) that is produced as a
byproduct of an active process of the industrial plant. The gaseous
stream may be substantially pure CO.sub.2 or a multi-component
gaseous stream that includes CO.sub.2 and one or more additional
gases. Multi-component gaseous streams (containing CO.sub.2) that
may be employed as a CO.sub.2 source in embodiments of the subject
methods include both reducing, e.g., syngas, shifted syngas,
natural gas, and hydrogen and the like, and oxidizing condition
streams, e.g., flue gases from combustion. Exhaust gases containing
NOx, SOx, VOCs, particulates and Hg would commonly incorporate
these compounds along with the carbonate in the precipitated
product. Particular multi-component gaseous streams of interest
that may be treated according to the subject invention include:
oxygen containing combustion power plant flue gas, turbo charged
boiler product gas, coal gasification product gas, shifted coal
gasification product gas, anaerobic digester product gas, wellhead
natural gas stream, reformed natural gas or methane hydrates, and
the like.
[0117] The volume of saltwater may be contacted with the CO.sub.2
source using any convenient protocol. Where the CO.sub.2 is a gas,
contact protocols of interest include, but are not limited to:
direct contacting protocols, e.g., bubbling the gas through the
volume of saltwater, concurrent contacting means, i.e., contact
between unidirectionally flowing gaseous and liquid phase streams,
countercurrent means, i.e., contact between oppositely flowing
gaseous and liquid phase streams, and the like. Thus, contact may
be accomplished through use of infusers, bubblers, fluidic Venturi
reactor, sparger, gas filter, spray, tray, or packed column
reactors, and the like, as may be convenient.
[0118] The above protocol results in the production of a slurry of
a CO.sub.2 sequestering precipitate and a mother liquor. Where
desired, the compositions made up of the precipitate and the mother
liquor may be stored for a period of time following precipitation
and prior to further processing. For example, the composition may
be stored for a period of time ranging from 1 to 1000 days or
longer, such as 1 to 10 days or longer, at a temperature ranging
from 1 to 40.degree. C., such as 20 to 25.degree. C.
[0119] The slurry components are then separated. Embodiments may
include treatment of the mother liquor, where the mother liquor may
or may not be present in the same composition as the product. For
example, where the mother liquor is to be returned to the ocean,
the mother liquor may be contacted with a gaseous source of
CO.sub.2 in a manner sufficient to increase the concentration of
carbonate ion present in the mother liquor. Contact may be
conducted using any convenient protocol, such as those described
above. In certain embodiments, the mother liquor has an alkaline
pH, and contact with the CO.sub.2 source is carried out in a manner
sufficient to reduce the pH to a range between 5 and 9, e.g., 6 and
8.5, including 7.5 to 8.2. In certain embodiments, the treated
brine may be contacted with a source of CO.sub.2, e.g., as
described above, to sequester further CO.sub.2. For example, where
the mother liquor is to be returned to the ocean, the mother liquor
may be contacted with a gaseous source of CO.sub.2 in a manner
sufficient to increase the concentration of carbonate ion present
in the mother liquor. Contact may be conducted using any convenient
protocol, such as those described above. In certain embodiments,
the mother liquor has an alkaline pH, and contact with the CO.sub.2
source is carried out in a manner sufficient to reduce the pH to a
range between 5 and 9, e.g., 6 and 8.5, including 7.5 to 8.2.
[0120] The resultant mother liquor of the reaction may be disposed
of using any convenient protocol. In certain embodiments, it may be
sent to a tailings pond for disposal. In certain embodiments, it
may be disposed of in a naturally occurring body of water, e.g.,
ocean, sea, lake or river. In certain embodiments, the mother
liquor is returned to the source of feedwater for the methods of
invention, e.g., an ocean or sea. Alternatively, the mother liquor
may be further processed, e.g., subjected to desalination
protocols, as described further in U.S. application Ser. No.
12/163,205; the disclosure of which is herein incorporated by
reference.
[0121] In certain embodiments, following production of the CO.sub.2
sequestering product, the resultant product is separated from the
mother liquor to produce separated CO.sub.2 sequestering product.
Separation of the product can be achieved using any convenient
approach, including a mechanical approach, e.g., where bulk excess
water is drained from the product, e.g., either by gravity alone or
with the addition of vacuum, mechanical pressing, by filtering the
product from the mother liquor to produce a filtrate, etc.
Separation of bulk water produces, in certain embodiments, a wet,
dewatered precipitate.
[0122] The resultant dewatered precipitate may then be dried, as
desired, to produce a dried product. Drying can be achieved by air
drying the wet precipitate. Where the wet precipitate is air dried,
air drying may be at room or elevated temperature. In yet another
embodiment, the wet precipitate is spray dried to dry the
precipitate, where the liquid containing the precipitate is dried
by feeding it through a hot gas (such as the gaseous waste stream
from the power plant), e.g., where the liquid feed is pumped
through an atomizer into a main drying chamber and a hot gas is
passed as a co-current or counter-current to the atomizer
direction. Depending on the particular drying protocol of the
system, the drying station may include a filtration element, freeze
drying structure, spray drying structure, etc. Where desired, the
dewatered precipitate product may be washed before drying. The
precipitate may be washed with freshwater, e.g., to remove salts
(such as NaCl) from the dewatered precipitate.
[0123] In certain embodiments, the precipitate product is refined
(i.e., processed) in some manner prior to subsequent use.
Refinement may include a variety of different protocols. In certain
embodiments, the product is subjected to mechanical refinement,
e.g., grinding, in order to obtain a product with desired physical
properties, e.g., particle size, etc.
[0124] FIG. 1 provides a schematic flow diagram of a process for
producing a CO.sub.2 sequestering product according to an
embodiment of the invention. In FIG. 1, saltwater from salt water
source 10 is subjected to carbonate compound precipitation
conditions at precipitation step 20. As reviewed above, term
"saltwater" is employed in its conventional sense to refer a number
of different types of aqueous fluids other than fresh water, where
the term "saltwater" includes brackish water, sea water and brine
(including man-made brines, e.g., geothermal plant wastewaters,
desalination waste waters, etc), as well as other salines having a
salinity that is greater than that of freshwater. The saltwater
source from which the carbonate compound composition of the cements
of the invention is derived may be a naturally occurring source,
such as a sea, ocean, lake, swamp, estuary, lagoon, etc., or a
man-made source.
[0125] In certain embodiments, the water may be obtained from the
power plant that is also providing the gaseous waste stream. For
example, in water cooled power plants, such as seawater cooled
power plants, water that has been employed by the power plant may
then be sent to the precipitation system and employed as the water
in the precipitation reaction. In certain of these embodiments, the
water may be cooled prior to entering the precipitation
reactor.
[0126] In the embodiment depicted in FIG. 1, the water from
saltwater source 10 is first charged with CO.sub.2 to produce
CO.sub.2 charged water, which CO.sub.2 is then subjected to
carbonate compound precipitation conditions. As depicted in FIG. 1,
a CO.sub.2 gaseous stream 30 is contacted with the water at
precipitation step 20. The provided gaseous stream 30 is contacted
with a suitable water at precipitation step 20 to produce a
CO.sub.2 charged water. By CO.sub.2 charged water is meant water
that has had CO.sub.2 gas contacted with it, where CO.sub.2
molecules have combined with water molecules to produce, e.g.,
carbonic acid, bicarbonate and carbonate ion. Charging water in
this step results in an increase in the "CO.sub.2 content" of the
water, e.g., in the form of carbonic acid, bicarbonate and
carbonate ion, and a concomitant decrease in the pCO.sub.2 of the
waste stream that is contacted with the water. The CO.sub.2 charged
water is acidic, having a pH of 6 or less, such as 5 or less and
including 4 or less. In certain embodiments, the concentration of
CO.sub.2 of the gas that is used to charge the water is 10% or
higher, 25% or higher, including 50% or higher, such as 75% or even
higher. Contact protocols of interest include, but are not limited
to: direct contacting protocols, e.g., bubbling the gas through the
volume of water, concurrent contacting means, i.e., contact between
unidirectionally flowing gaseous and liquid phase streams,
countercurrent means, i.e., contact between oppositely flowing
gaseous and liquid phase streams, and the like. Thus, contact may
be accomplished through use of infusers, bubblers, fluidic Venturi
reactor, sparger, gas filter, spray, tray, or packed column
reactors, and the like, as may be convenient.
[0127] At precipitation step 20, carbonate compounds, which may be
amorphous or crystalline, are precipitated. Precipitation
conditions of interest include those that change the physical
environment of the water to produce the desired precipitate
product. For example, the temperature of the water may be raised to
an amount suitable for precipitation of the desired carbonate
compound(s) to occur. In such embodiments, the temperature of the
water may be raised to a value from 5 to 70.degree. C., such as
from 20 to 50.degree. C. and including from 25 to 45.degree. C. As
such, while a given set of precipitation conditions may have a
temperature ranging from 0 to 100.degree. C., the temperature may
be raised in certain embodiments to produce the desired
precipitate. In certain embodiments, the temperature is raised
using energy generated from low or zero carbon dioxide emission
sources, e.g., solar energy source, wind energy source,
hydroelectric energy source, etc. While the pH of the water may
range from 7 to 14 during a given precipitation process, in certain
embodiments the pH is raised to alkaline levels in order to drive
the precipitation of carbonate compound as desired. In certain of
these embodiments, the pH is raised to a level which minimizes if
not eliminates CO.sub.2 gas generation production during
precipitation. In these embodiments, the pH may be raised to 10 or
higher, such as 11 or higher. Where desired, the pH of the water is
raised using any convenient approach. In certain embodiments, a pH
raising agent may be employed, where examples of such agents
include oxides, hydroxides (e.g., sodium hydroxide, potassium
hydroxide, brucite), carbonates (e.g. sodium carbonate) and the
like. The amount of pH elevating agent that is added to the
saltwater source will depend on the particular nature of the agent
and the volume of saltwater being modified, and will be sufficient
to raise the pH of the salt water source to the desired value.
Alternatively, the pH of the saltwater source can be raised to the
desired level by electrolysis of the water.
[0128] CO.sub.2 charging and carbonate compound precipitation may
occur in a continuous process or at separate steps. As such,
charging and precipitation may occur in the same reactor of a
system, e.g., as illustrated in FIG. 1 at step 20, according to
certain embodiments of the invention. In yet other embodiments of
the invention, these two steps may occur in separate reactors, such
that the water is first charged with CO.sub.2 in a charging reactor
and the resultant CO.sub.2 charged water is then subjected to
precipitation conditions in a separate reactor.
[0129] Following production of the carbonate precipitate from the
water, the resultant precipitated carbonate compound composition is
separated from the mother liquor to produce separated carbonate
compound precipitate product, as illustrated at step 40 of FIG. 1.
Separation of the precipitate can be achieved using any convenient
approach, including a mechanical approach, e.g., where bulk excess
water is drained from the precipitated, e.g., either by gravity
alone or with the addition of vacuum, mechanical pressing, by
filtering the precipitate from the mother liquor to produce a
filtrate, etc. Separation of bulk water produces a wet, dewatered
precipitate.
[0130] The resultant dewatered precipitate is then dried to produce
a product, as illustrated at step 60 of FIG. 1. Drying can be
achieved by air drying the filtrate. Where the filtrate is air
dried, air drying may be at room or elevated temperature. In yet
another embodiment, the precipitate is spray dried to dry the
precipitate, where the liquid containing the precipitate is dried
by feeding it through a hot gas (such as the gaseous waste stream
from the power plant), e.g., where the liquid feed is pumped
through an atomizer into a main drying chamber and a hot gas is
passed as a co-current or counter-current to the atomizer
direction. Depending on the particular drying protocol of the
system, the drying station may include a filtration element, freeze
drying structure, spray drying structure, etc.
[0131] Where desired, the dewatered precipitate product from the
separation reactor 40 may be washed before drying, as illustrated
at optional step 50 of FIG. 1. The precipitate may be washed with
freshwater, e.g., to remove salts (such as NaCl) from the dewatered
precipitate. Used wash water may be disposed of as convenient,
e.g., by disposing of it in a tailings pond, etc.
[0132] At step 70, the dried precipitate is refined, e.g., to
provide for desired physical characteristics, such as particle
size, surface area, etc., or to add one or more components to the
precipitate, such as admixtures, aggregate, supplementary
cementitious materials, etc., to produce a final product 80.
[0133] In certain embodiments, a system is employed to perform the
above methods.
[0134] Following production of the CO.sub.2 sequestering component,
e.g., as described above, the CO.sub.2 sequestering is then
employed to produce a non-cementitious composition of the
invention, e.g., as described above.
Utility
[0135] Compositions of the invention find use in a variety of
different applications, as reviewed above. The subject methods and
systems find use in CO.sub.2 sequestration, particularly via
sequestration in a variety of diverse man-made products. By
"sequestering CO.sub.2" is meant the removal or segregation of
CO.sub.2 from a gaseous stream, such as a gaseous waste stream, and
fixating it into a stable non-gaseous form so that the CO.sub.2
cannot escape into the atmosphere. By "CO.sub.2 sequestration" is
meant the placement of CO.sub.2 into a storage stable form, where
the CO.sub.2 is fixed at least during the useful life of the
composition. As such, sequestering of CO.sub.2 according to methods
of the invention results in prevention of CO.sub.2 gas from
entering the atmosphere and long term storage of CO.sub.2 in a
manner that CO.sub.2 does not become part of the atmosphere.
[0136] While preferred embodiments of the present invention have
been shown and described herein, it will be obvious to those
skilled in the art that such embodiments are provided by way of
example only. Numerous variations, changes, and substitutions will
now occur to those skilled in the art without departing from the
invention. It should be understood that various alternatives to the
embodiments of the invention described herein may be employed in
practicing the invention. It is intended that the following claims
define the scope of the invention and that methods and structures
within the scope of these claims and their equivalents be covered
thereby.
* * * * *